It's just alsways been my policy... If the OS is screwed up, you normally don't 'fix' it. System restore, driver re-installs, virus scans, and ad-ware scans... sure do 'em. But when you have probs with explorer.exe or a persistant BSOD or 'illegal operations'. Then you know the OS is hosed. I just never feel confidant working on a machine with a patched up OS, and usually, you will still have little residual problems that you will have to live with. If you think about it, it broke because of something, and you still don't know what that is. OS re-installs can be annoying, but after you do it a few times, it isn't so bad.