I've never had to do it.
I'm giving my old PC to a friend so I'm going to do a reinstall and let her start from fresh.
Obviously, there are tons of walkthroughs on the web, but I still have a couple of questions:
1. All I have is a Windows XP OEM disc. Is the fact that it's OEM going to cause some problems? Essentially, is the reinstall going to delete the boot info? That would be bad as the OEM disc doesn't have it.
2. Anything else I need to know prior to doing this?