Formating your hard drive and installing XP - from Lifehacker

There is a great article posted today over at Lifehacker on how to reformat your hard drive and install Windows XP.

As someone that has had to do this on more than one occasion, it is not a trivial undertaking. However, Gina does a great job walking you through the process, you might want to bookmark their page for future reference just in case :) Step one is about backing up your data, there's more information about that here.