Yes, you can reinstall XP with the just the CD. Assuming your motherboard can boot from a CD, you should be fine. Go into your BIOS, and change the boot order, so the CD-ROM gets first boot, then insert the CD, and restart. The computer should boot from the CD. (Depending on your motherboard, it may ask you to "press and key to boot from CD". Press the key, and then it should load Windows XP from the CD. Then follow the steps to Install Windows XP. It will ask you which drive you want to install XP on, click the C: drive. Then it will say that there is already a copy of Windows XP detected, select continue with installation. Then it will reformat the drive, and copy over the files from the CD to the hard drive. Then it will reboot and finish the installation. Good luck.