Strictly speaking, nothing to do with the Suse version - other than the fact that they haven't fixed it's obviously poorly designed installer.
Windows will
only boot from the primary disk (yeah I know; we'll get to that). Grub fools it via the map directive as below (watch the blanks) - suggest you also include the rootnoverify
Code:
title Windows
map (hd0) (hd1)
map (hd1) (hd0)
rootnoverify (hd1,0)
makeactive
chainloader +1
That should fix the immediate problem.
As for why Windows won't boot from it's own disk, sounds like you installed grub more than once, and hit the MBR of that (Windows) disk. Easy fixed - set it as primary in the BIOS, boot the XP CD, and get into recovery centre (??) and run fixmbr.
Won't affect your Linux install - if you hit the correct disk
Set the BIOS back, and off you go.