|You can boot up with the XP disk to do the reinstall. You may be able to do a repair install. If not, delete the existing partition and then recreate it. That will have the affect of wiping the drive so you can do a fresh install.|
Or, if the OS was installed when you got it, there may be a restore partition on the hard drive or maybe you have restore disks. You should probably check whatever paperwork came with it or post back info on about your system. A restore should have all the drivers so you wouldn't need to hunt them down later.
Whatever drivers XP doesn't have you can download from the motherboard or system manufacturer's site (if it's something like a dell or gateway). For any add-on cards you can go to the card manufacturer's site. You can download any necessary drivers on the computer you're using now, burn them to a cd, flash drive or other removable media and use them on the other computer.
You're not really green until you're soylent green.