Ok, thank you very much for the clear explanation. These days, if not tomorrow, I will do it and let you know what has happened

Cool. Keep asking questions. It's the best way to learn.

If you change the HDDs around, then /etc/fstab won't be correct. You'll also have to change "/dev/hdb1" with "/dev/hda1" (and vice versa if you have the Windows partition in there). It should be changed right before you shut the computer down before you do the swap.

D'oh!!!

You're VERY correct. Forgot about fstab...

Thank you very much for your responsiveness. I swapped my harddrives and reinstalled, because I had not remembered to change /etc/fstab file. At first I chose expert lilo installation and chose to install lilo on a formatted floppy, so that if something goes wrong I have the chance to coorect it before I install lilo to the MBR of /dev/hda. When I chose Windows at the lilo prompt, everything froze as before. Slackware loaded without problem. I ran "lilo" and it gave the following warnings: "Warning: boot record relocation beyond BPB is necessary: /dev/fd0"
"Warning: The boot sector and map file are on different disks".
Then I ran "liloconfig" and installed lilo right in the MBR of /dev/hda. When I chose Windows at the prompt, nothing happened - the system froze. Then I rebooted, loaded Slackware and chose simple lilo installation. Again windows could not be loaded. I then made a fresh Slackware reinstallation again, chose expert lilo installation and installed it to the MBR of /dev/hda. After rebooting again lilo could not load Windows. Everything freezes after I choose "windows" at the prompt and there is no error message or warning at all. Now even after a fresh Slackware installation I am not able to load Windows . I really do not know what do do now. please help me
I will now introduce my current configuration :
This is my /etc/fstab:
/dev/hda5 swap swap defaults 0 0
/dev/hda1 / reiserfs defaults 1 1
/dev/hda6 /opt reiserfs defaults 1 2
/dev/hda7 /var reiserfs defaults 1 2
/dev/hda8 /usr reiserfs defaults 1 2
/dev/hda9 /home reiserfs defaults 1 2
/dev/hdb1 /WinC ntfs ro 1 0
/dev/hdb5 /WinD vfat defaults 1 0
/dev/hdc /mnt/cdrw auto noauto,user,ro 0 0
/dev/hdd /mnt/cdrom auto noauto,user,ro 0 0
/dev/fd0 /mnt/floppy auto noauto,user 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
proc /proc proc defaults 0 0

This is the product of fdisk /dev/hda:

Disk /dev/hda: 160.0 GB, 160041885696 bytes
255 heads, 63 sectors/track, 19457 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/hda1 1 1246 10008463+ 83 Linux
/dev/hda2 1247 17538 130865490 5 Extended
/dev/hda5 1247 1490 1959898+ 82 Linux swap
/dev/hda6 1491 2736 10008463+ 83 Linux
/dev/hda7 2737 3982 10008463+ 83 Linux
/dev/hda8 3983 7469 28009296 83 Linux
/dev/hda9 7470 17538 80879211 83 Linux

and this about /dev/hdb:

Disk /dev/hdb: 41.1 GB, 41110142976 bytes
255 heads, 63 sectors/track, 4998 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/hdb1 * 1 3749 30113811 7 HPFS/NTFS
/dev/hdb2 3750 4998 10032592+ f W95 Ext'd (LBA)
/dev/hdb5 3750 4998 10032561 b W95 FAT32

I will be so thankful if someone suggests me some remedy.

OK...

Reread everything.

Lets start with the basics, and tell me if I'm wrong:

/dev/hda contains Linux

/dev/hdb contains Windows

Can Windows boot on its own if the other drives are not connected (make XP the /dev/hda, or "Primary Master")? Reason why I ask this is because different Windows/BIOS combos makes Windows puke when trying to boot it from anything but /dev/hda. (See how /dev/hda means more than "Primary Master'? I think it's easier to understand...)

Here are some possible steps:

Make Windows boot all on its own, with no other hardrives in the system except the Windows one.

Attach the Slackware drive as /dev/hdb

Boot Windows again. (Just to make sure the Computer Gods are still smiling...)

Boot Slackware with cd1, and run 'liloconfig' in exprt mode, tell it the various junk, and install it to MBR of /dev/hda. Edit fstab on the linux drive, only having the Windows and whatever is needed for your partition setup to allow Linux to run (In other words, make sure the drives that are NOT connected to the system yet to try to be mounted by fstab)

DON'T run lilo again. It was already run when 'liloconfig' was run.

Try to boot Windows again.

Try to boot Slackware.

Then add in other drives into your system, and editing fstab to reflect thoise additions.

Retry Windows and Slackware.

Let us know.

As I said, maybe Windows just plain wants to be on /dev/hda, and make sure the bios boots /dev/hda first...

Yes, Windows is on /dev/hdb and Slackware Linux is on /dev/hda. When I set BIOS to boot /dev/hdb first, then Windows loads. But if I set it to boot /dev/hda first, then the lilo prompt appears with "Slackware" and "Windows" options. When I choose "Windows", it just types "Loading Windows" and then the cursor goes on blinking forever ...
I've already posted my current configuration, and for a complete idea of my boot settings, here is the lilo.conf:

# LILO configuration file
# generated by 'liloconfig'
#
# Start LILO global section
boot = /dev/hda
#compact # faster, but won't work on all systems.
prompt
timeout = 300
# VESA framebuffer console @ 1024x768x256
vga = 773
# Normal VGA console
# vga = normal
# VESA framebuffer console @ 1024x768x64k
# vga=791
# VESA framebuffer console @ 1024x768x32k
# vga=790
# VESA framebuffer console @ 1024x768x256
# vga=773
# VESA framebuffer console @ 800x600x64k
# vga=788
# VESA framebuffer console @ 800x600x32k
# vga=787
# VESA framebuffer console @ 800x600x256
# vga=771
# VESA framebuffer console @ 640x480x64k
# vga=785
# VESA framebuffer console @ 640x480x32k
# vga=784
# VESA framebuffer console @ 640x480x256
# vga=769
# ramdisk = 0 # paranoia setting
# End LILO global section
# Linux bootable partition config begins
image = /boot/vmlinuz
root = /dev/hda1
label = Slackware
read-only # Non-UMSDOS filesystems should be mounted read-only for checking
# Linux bootable partition config ends
# Windows bootable partition config begins
other = /dev/hdb1
label = Windows
# map-drive = 0x80
# to = 0x81
# map-drive = 0x81
# to = 0x80
table = /dev/hdb
# Windows bootable partition config ends

I do not want to touch the Windows hard drive at all, for I have too precious data there to risk it. And besides I do not feel very comfortable with reinstalling Windows.
Isn't there some way to make lilo capable of booting Windows without installing lilo to the MBR of the Windows drive?
Today I found in the kde control center some options concerning lilo configuration. Probably the key is somewhere in those settings there? Here is what kde says about the lilo configuration there:

Configuration ok. LILO said:
LILO version 22.5.9 (test mode), Copyright (C) 1992-1998 Werner Almesberger
Development beyond version 21 Copyright (C) 1999-2004 John Coffman
Released 08-Apr-2004 and compiled at 00:18:50 on May 21 2004.
Warning: LBA32 addressing assumed
Reading boot sector from /dev/hda
Using MENU secondary loader
Calling map_insert_data
Boot image: /boot/vmlinuz
Added Slackware *
Boot other: /dev/hdb1, on /dev/hdb, loader CHAIN
Added Windows
The boot sector and the map file have *NOT* been altered.

So, if you need some more info, let me know. Just for now I will load Slackware using lilo, and if I need to go to windows I will have to set BOIS to boot the windows drive first. This is not the best solution, so I would be glad to receive some helpful advice. For touching BIOS too often is not healthy ...

OK. Here is my previous post:So why is Windows still on /dev/hdb? If you followed instructions, it would HAVE to be /dev/hda.

Once more (and very last time I will repeat myself):

Rejumper drives so Windows is /dev/hda, Linux is /dev/hdb, and then reset bios so it boots /dev/hda.

Make sure windows boots.

Boot with cd1, rerun 'liloconfig', and INSTALL ON MBR OF /dev/hda and edit fstab.

It should work then.

The issue is that you are trying to boot /dev/hdb, and while Windows is fooled into thinking it is the first harddrive, Linux is NOT fooled, so it is confusing the lilo program

Again, reconfigure/rejumper your drives so Windows is the "Primary Master", and Linux is "Primary Slave". Then reset the bios to boot to "Primary Master". In other words, make it like everything was before you started changing stuff, and make it boot right.

If you post back that "my bios is booting /dev/hdb" or "windows is on /dev/hdb" it means YOU ARE NOT FOLLOWING WHAT IS BEING TOLD TO YOU.

And if that is the case, do it on your own. If you do not listen, no amount of help will resolve this.

OK, the prblem is that I DO NOT WANT TO INSTALL LILO TO THE MBR OF THE WINDOWS DRIVE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
If I make the Windows drive master and install lilo to the MBR of /dev/hda, this means I am have insatlled lilo to the MBR of the Windows drive, something that I DO NOT WANT TO DO!!!!!!!!!!
Isn't there some way to make lilo boot Windows without installing it to the MBR of the windows drive?

It looks like not on your system.

Sometimes, you just gotta do it. I do. 99% of the dual booters out there do it. If you don't want to, then just use a floppy to boot slackware, and otherwise Windows will boot.

It's a bios/Windows issue. Windows wants to be /dev/hda, and telling the bios to boot /dev/hdb does not fool linux. You have to make a choice:

Install lilo to mbr of /dev/hda (Windows) or:

Only boot Slackware with a lilo floppy.

Ok, but if something bad happens with the lilo installation on the mbr of the windows drive, and neither operating system boots, will there be some way to boot windows? For Slackware I will use the slacware cd1 and boot it from there, but what about windows?
Will it be possible to boot windows in case the lilo installation in its MBR does not work correct?

YOur stubborness at not trying it the way everyone does it makes you take lots more risks, friend. lilo itself will reinstall your windows MBR if you mess up.
The MBR is not part of the Windows file system. Every OS will treat the first sector as a *boot* sector, with or without partition table.
lilo will back up the MBR when you install it. If it doesn't work, you can boot the machine with most any rescue floppy or linux installation or live CD and restore the backup.
Honestly, what you have already done is *way* more risky than just following the normal way.

Ok, I did what you instructed me to and finally I was at a success. I rejumpered my hard drives so that again the windows drive is master and the linux one is slave. Before installing lilo to the MBR of the windows drive, I
installed it to a floppy. The installation from the floppy worked perfectly, so I edited the global section of lilo.conf, replacing "boot=/dev/hd0" to "boot=/dev/hda". then I ran "lilo" and it said the following:
"Warning: the boot sector and the map file are on different disks
Added Slackware *
Added Windows".
Then I rebooted and lilo worked perfectly. The only thing is that somewhat slowly starts the lilo prompt, there are about 10 seconds scratchy,rasping sounds and then the prompt appears. Probably the reason is that the boot sector and the map file are on different disks, what says the lilo warning. Have you got some idea how to adjust that?
However, now lilo works and does not stop working properly after I run "lilo".
The deduction of my efforts these days can be summarized as follows:
If you have a multi-booting system with Windows, you have to make the Windows drive primary master and install the boot loader to the MBR of the Windows drive. LILO MUST BE IN THE MBR OF THE WINDOWS DRIVE IN ORDER TO BE ABLE TO LOAD WINDOWS. At least it is like that on my system.
Could you explain to me what does the warning "the boot sector and the map file are on different disks" mean and how to settle the boot sector and the map file on one and the same disk?

It means that Linux is on disk 2 and the lilo mbr is on disk 1. Not really an error, it happens all the time. Just a warning. And no fix as far as I know.

Ok, thank you very much indeed. At last I have a really working dual booting system. I am curious about something else. In configurations where both Linux and Windows are on one and the same hard drive, will installation of the lilo to the Linux root partition be successful? How could it be successful, since BIOS looks for the boot sector first? What would you recommend if I have to install Linux on such a system, so that it is dual booting with Windows? I would be glad if an instalation to the root partition works, but would like to consult somebody else, so that I spare some unnecessary experimentation ...