I've been using Windows 7 on my desktop PC for 3 years, and I have to say thanks to Chrome, Steam & Dropbox I think, in case of an emergency format or reinstall, everything could be pretty easy, as long as you save your files on the cloud. Using and SSD for Windows and another HDD for your photos, music, videos, steam games.
Maybe before formatting, you could save important files on dropbox, or doing a backup of your iTunes database if you care about playlists, plays count, smart playlists, etc. Saving serial numbers, configuration files.
I wish for some kind of skydrive integration in Windows 7 SP1 like Windows 8.1, where all your settings are stored in the cloud, that was the only thing that I really enjoyed about Windows 8.
But like I said before, reinstall just when it's an emergency, like when Windows is getting slow because of a virus, windows update, system error or some kind of bad software installation. But in that case sometimes it's better to going back to a certain restore point.
Cloud backup or physical media it's always recommended.