It appears that Macs have a utility that can do similar to windows restore but it has to have been installed and manually backed up onto another partition,similar to ghosting I would summise.
I came across this from a Mac user saying what features from XP he would like to see included in future Mac OSs :
System Restore: This isn't quite the same as the Restore CDs that come with a Mac (which can return the computer to factory condition in a single process). The Windows XP version of System Restore is more akin to Power On Software's Rewind. Microsoft's version takes periodic snapshots of the condition of your system as you install new applications and drivers. If something goes wrong, you can return the system to a previous state, just before all hell broke loose. Yes, there's a third party solution on a Mac (or will be when Power On comes up with a Mac OS X version of Rewind). But doing it on the system level has got to be a real plus and one sure way to help in the event of a disaster.
As Gem said its system restore anyway not file restore.You would need a very large drive if XP was going to automatically save all the info on your PC every time it or you created a restore point.
I assume she hadnt backed that folder or file up anywhere Clive?