[Bozos of Bones]

Unless the viruses somehow wrote themselves in an unerasable part of the disk(low chances), a format will get rid of them. You can not use the back-up disks to install XP on another computer, Back-up disks contain computer-specific information about the setup and the hardware installed on the PC, and they may not be used to install XP on a different system. They may not be used to install XP on the same system even. To format, first use the windows right-click on all the other drives except for drive C, and choose the format option. Then, place the XP installation disc in, and restart the computer. While following the installation instructions, choose to completely format the drive you are installing to.