Edit: Guess what I found and umm, yeah, messed up my own computer for a moment (XP Install CD).
OK, it didn't offer to repair my installation while I was running through setup but it did manage to corrupt my file system (Could be because I was using the Pro version instead of the Home version)
Forgot that this computer didn't have Pro on it, it came loaded with the Home version.
Anyhow, the only choice you have is to figure out or reset the Admin password, load the Recovery Console and use the
Bootcfg /rebuild command, trust me, it works, just fixed my corrupted file system.
Well, there is another option but it's not pretty, delete or format partition and start from scratch.
If you follow all the way though the installation process without formating, it will most likely create a Windows.000 folder and install a fesh copy of windows XP, your programs won't appear in Windows and more than likely won't work if you explore to their folder and try to launch them.
The only other thing it may do is install a fresh copy of Windows over the existing one, same result though, files will be there but none of them will work because they aren't installed properly.
Nick