Best and easiest way to do a backup is back up C:\users\"your user acct"... what ever the "acct name" may be.... that should save everything you could possibly need to save and then you can reload windows fast and easy - and drag n drop that folder right back into windows, make sure you make another user acct with the same name....
Shouldn't take more then an hour - I hope you not using Internet Explorer as your browsers and you have a decent virus protection.... - I use Eset NOD32 antivirus, it uses minimal resources and I never - see it pop up anything, maybe a couple times a year running firefox with adblock add on....