|Depends. If you want to save data then you may have to boot to some live cd and see if you can access any of the old data.|
Normally you can't easily load xp twice. It may be that it was loaded on a secondary partition or recovery partition.
She needs to get a live linux cd and run it until someone can help out.
If no data is needed then simply reload xp and apps.
Why did it take me over a year to phone in a problem to ATT?