Just my thoughts but if the USB ports work (show up) then they're obviously enabled in the BIOS so resetting the BIOS shouldn't resolve anything. An empty BIOS battery is easily detected as most MBs start with an error message about the time/date being wrong in this case.
This sounds like a Windows issue relating to the location of your installation files. Have you tried borrowing a Win XP cd and pointing at that during the sequence?