RootRepeal killed system disk?

Hi all. On my WinXP system that the kids use, I noticed it just recently began rebooting at times and other laggy behavior, so I decided to run through the read me first. All was going well enough, two minor seeming things found and cleaned, then I came to RootRepeal. I hadn't run this one before.
I ran it, system froze for a while, then a blank window with just a title bar saying RootRepeal came up, and I left it for quite a while. Next I knew, the system had rebooted and said "DISK BOOT FAILURE, INSERT SYSTEM DISK AND PRESS ENTER". Agh!!
I don't have another XP system here and have NO idea where my boot disks are, so I'll have to wait to make a boot disk tomorrow at work to check it out further. I'm sure I have another bootable drive around somewhere, but it's too late to start into that, so I thought I'd see if others had experienced this before.

Thanks!
Samantha