Welcome to LQ!
Not sure I understand your question, but here goes...
This box has 2 identical drives. The first one, /dev/hda has 2 Windoze OSes.
The second drive, /dev/hdc has Slackware Linux. The bootloader is actually
in the MBR of /dev/hda, so "it's on the first drive." You only have to tell it this
when you setup LILO. You need to install the Windoze OS first, and the Linux
OS last, because the Windoze bootloader will overwrite LILO and you won't
be able to boot your shiny new Linux system. When you configure LILO just
put LILO in the MBR (Master Boot Record) which will be /dev/hda if your XP
system is the master drive on the first controller, and then tell LILO which of
your partitions is the / (root) partition of your Linux system. Btw, LILO is the
boot loader (unless you're using GRUB, that is.)
When you install the Linux OS, be sure you put it on the second hard drive.
If you have both hds on the same ribbon cable, it's /dev/hdb
/dev/hda = primary controller, master drive
/dev/hdb = primary controller, slave drive
/dev/hdc = secondary controller, master drive
/dev/hdd = secondary controller, slave drive
As for partitions and file systems, NTFS is a journaling file system which works
best with Win 2000 and Win XP. However, you can not reliably write to NTFS
from Linux, though you can read it. I setup with W2K and XP on separate
NTFS partitions, and then I make one DATA partition that is NTFS for files that
I don't need to share with Slack; and another DATA partition that's FAT32 for
files that I do want to share with Slack. Files created in Slack that I want to
share with the Windoze OSes can also be copied/saved/moved to that FAT32
part. NB: Windoze cannot read any Linux filesystems, but Linux can read FAT,
FAT16, FAT32 and NTFS Windoze filesystems.
Hope this answers your question. You should read and learn more about LILO.
If you need more help, post back and someone will give it a go!