LiveCDs are great - an operating system that runs from the CD drive.  One problem with LiveCDs is that they often don't support read/write access to your NTFS format volumes.  So what would be ideal is WindowsXP on a LiveCD.

http://www.ubcd4win.com/faq.htm

I haven't tried it since I just found it a few minutes ago but it looks good.  I've been using ERD Commander 2005 for when I get my system into a problem where windows won't start or I need to change files that windows won't let me change while it's running.

http://www.winternals.com/Products/AdministratorsPak/Default.aspx - more info on ERD Commander 2005 there.