I always make a DVD full of programs I know Ill need (WinZip, Photoshop, AIM, PeerGuardian, Limewire Pro, etc) and their associated 'addons/patches'

and then backup my documents to another DVD and scrub it and reload it. That way, when your back up, its as easy as reinstalling everything and copying your documents back on.
For the past 3-4 times Ive reformatted Ive always told myself that I want to make a mirror of the drive at this point but Ive been too lazy. Just an idea. A mirror and your 'essential programs' DVD could possible clean things up in a jiff.