well as I belive they have DVD \ CD rom in thier computer then you can use partition magic or Fdisk or Smart FDISK
all this you can find on Hiren Boot cd just download it and burn on a cd
boot from this cd
start Partition magic and everything will turn pink in a blank
afterward you can install system or whatever you want to do....
note: Hiren boot full of useful tools for everything.
otherwise you can you your xp be cd and start installing system and during the installing you will be prompted to create partition or format and this save time and download for you