I have just installed Suse 9.1 on a master HD with WinXP on it - I also have a second hard drive with an older installation of WinXP which I still use. I want to be able to make the choice as to which OS boots from the initial Grub menu. I understand that grub needs to be 'fooled' to boot the WinXP from the second drive and to that end after much searching and without fully understanding how it is meant to accomplish this trick I found and added this to the boot/grub/menu.1st file:

title Old Windows
map (hd0) (hd1)
map (hd1) (hd0)
rootnoverify (hd1,0)
makeactive
chainloader +1

but it still boots directly into the WinXP on the first HD - but strangely without having to go through the menu (which appears after the grub menu) I use to choose between this and the other WinXP.

Anybody have any advice?

You have swapped the drive order but did not swap location of the root partition - try using:
title Old Windows
map (hd0) (hd1)
map (hd1) (hd0)
rootnoverify (hd0,0)
makeactive
chainloader +1

Sorry, still the same situation - I changed the "rootnoverify (hd1,0)" to "rootnoverify (hd0,0)" and it still boots directly to the newer WinXP on the first drive - without the menu option of choosing the older install.