Does it delete EVERYTHING on the computer or what, everything as in programs added after brought.
Restore disk does that yes. As in return it to factory conditions. But depends what type it is from, some of the older versions does delete all, but some newer ones just reinstall Windows Xp.
As long as you don't format your disk they'll still be there.
Your hard disk. XP will ask you if you want to do that when you install it. Don't, if you want to keep your data and programs.