LinuxQuestions.org - Triple boot w/ GRUB

I am trying to run a triple boot with WinXP, Slackware, and Rubyx.

My partition scheme is as follows:
Device Boot Start End Blocks Id System
/dev/hda1 * 1 956 7679038+ 7 HPFS/NTFS
/dev/hda2 957 4864 31391010 f W95 Ext'd (LBA)
/dev/hda5 957 3422 19808113+ 7 HPFS/NTFS
/dev/hda6 3423 3946 4208998+ 83 Linux
/dev/hda7 3947 4471 4217031 83 Linux
/dev/hda8 4472 4733 2104483+ 83 Linux
/dev/hda9 4734 4864 1052226 82 Linux swap

WinXP on hda1, with a NTFS data drive at hda5.
Slackware / at hda6
Rubyx / at hda7
/home at hda8
swap at hda9

my menu.1st file for GRUB is:
default=0
timeout=10

title WindowsXP
rootnoverify (hd0,0)
chainloader +1

title Slackware
root (hd0,7)
kernel /boot/vmlinuz root=/dev/hda6

title Rubyx
root (hd0,8)
kernel /kernel/bzImage root=/dev/hda7

First off, I try to install the grub files on /home/boot/grub, because it is the most stable partition. At the grub prompt, I type root (hd0,9), I get "Error 22: No Such Partition". Well, this partition DOES exists, I even have files in it. So, I don't know WHY this happens, but I move my grub files from /home/boot/grub to /boot/grub. Run root (hd0,7), everything seems okay. Then I run setup (hd0), and install GRUB.

I reboot, get my three possible choices. WinXP boots okay. Slackware does not. I get a message saying it can't find the kernel at /boot/vmlinuz, but I KNOW that it exists there on hda6. Lastly, when Rubyx is selected, I get a message saying that the file system is not recognized (even though fdisk tells me it is ext3, and I can mount it and r/w it just fine... after all, Rubyx is installed on it).

Anyway, I can't figure out what to do next. Why can't I have grub install on (hd0,9)? Why can it not find /boot/vmlinuz for Slackware, even though it is there? Why does it not think the Rubyx parition is a valid fs type?