Boot Camp is just a formatting tool that will partition and create a format as FAT32 while booted in Mac OS X.
If you, say, create an MSDOS (FAT) partition through Disk Utility, you can insert your Windows System Disc and hold down the "C" key to boot to it. Don't forget to press the Any key!
Depending on which version of Windows you have, you can boot up to it, and press the R key (it will say on the screen) to start up the repair services (disk scanner, and I believe command prompt). You would then need to locate and replace the HAL.DLL from the CD with the one on your C drive. Otherwise I don't think there is any way else to fix it (unless you maybe take out the drive and plug it into another Windows machine). The one major problem that I've personally experienced with Windows is that HAL bullsnot. I swear that file has a mind of its own...