Step 1:Start up your computer (make sure the windows xp installation disk is inside your computer)
Step 2:Press F12, F3 or another combination to open your BIOS (Depends on what computer you have)
Step 3:Go in your BIOS to 'advanced'
Step 4:Change 'First Boot Device' to [CDROM]
Will look like this: (depends on what computer and BIOS system you have)
Step 5:Go back to the main menu
Step 6:Select 'Safe & Exit Setup'
Step 7:Reboot your computer
Step 8:Follow the steps through the windows installation
Note: If you have any problems with this, tell it here to us, then we find a other solution.