Hi. I will suggest caution when dealing with dual-boot systems.
I had a dual-boot system consisting of Win98 and Win 2000 Pro until last Friday when I reinstalled Win 98. When I did this, I lost my ability to boot into Windows 2000. I don't know the technical details, but I think reinstalling Win 98 overwrote part of the startup routine that permitted me to choose if I wanted to boot into Win 2000 or Win 98.
Before doing I say you get a definite answer/advice from someone who knows what they're talking about, and you should be prepared to reinstall your XP partition.
CHEERS!