As an IT professional, I just have MS Security Essentials running at all times. I also use Malwarebytes AntiMalware and Spybot regularly to clear the PC of anything MS has missed. To date I have not had a single attack take me down and have been running this PC daily since I bought it two years ago.
totalvirus.net or .com. not sure! you can upload a single file and get it scaned on the cloud!
Also Comodo antivirus is pretty good! It has a function in defense + allowing you to run suspicious programs in the cloud system of comodo dns. to check for infection and without exposing your computer!