Do a quick search for 'best free anti virus',
malwarebytes anti-malware is pretty good,
other than that i suggest installing ubuntu and running that instead of windows
also i would get rid of mcafee, don't trust those bastards, for all i know they're running covert ops against your pc so that you will buy their next product
The Will, check out the Official Home of Will's GameDay Art: http://tinyurl.com/thewillgameday