Really stupid on my part, but did it anyway...
My boot drive wasn't C, and instead was F. Using Partition Magic on WinXP, I reassigned the drive letters, even though a popup said "Doing this may cause your system to not boot" or something very similar. Well sure enough, I can't boot off that drive. I believe right after the big WinXP loading screen, a Partition Magic screen comes up saying something along the lines of "Batch file cannot be run. Make sure your System32 folder is not corrupt or
other word."
Anything I can do to change the letters?