Well if its only 3 gig and shes not far away, why not take her drive out and put it as a slave to yours and either write it to cd/dvd or simply transfer to yours then back again after youve reinstalled xp.
Actually I wouldnt run a pc on XP with a 3 gig drive, I recently had an old pc with a 2.1 gig drive that I wanted to see what the SP2 upgrade was like so I installed XP inc SP1 on it and then tried to use the SP2 cd from MS to install it on it.
It came up with the message that there was insufficient space to unpack it to for it to be able to install.
It did take a later version of XP which had SP2 included but used almost all the 2.1 gig just for that and I didnt add any other programs at all