What I did, and which solved many of my many problems with Vista, was to set up a dual-boot. Make a partition for XP, then install it.
WARNING: You REALLY need to look this up on the web. When you install XP, Vista will no longer be available UNTIL you run a program that is free for download, which will fix Vista and set up a boot menu.
I made a topic on this dual boot setup here:
http://www.abandonia.com/forum/index.php?s...st&p=286172