I use nod32 by eset security I analyze threats and test the antivirus software and so far nod32 security has come out top for detecting and removing viruses, but have also found they find different things Norton is best for cookies ect. And I use malware bytes as my weapon on malware and super antispyware for spyware and also like web root as well in my opinion nod32 get the vote as it is best detecting on infected links and avast is also very good. Norton is a great tool and sells many great products to I just brought the new Norton ghost and very pleased with the product. Kind Regards
For windows bare-metal - NOD32 (aka eset smart security)
For windows VM - AVG free
Spybot S&D and MSSE offline bootable usb for friend&family support etc.
Linux - avgscan (although it really isn't needed)