From Howtogeek.com :
http://www.howtogeek.com/181342/whats-the-best-antivirus-and-how-do-i-choose-one/

Test Report for home user from
http://www.av-test.org/en/tests/home-user/

For free product, bothAVG Free Edition 2013 and Avast:Free Antivirus 8 are good.
For Commercial Products: Kaspersky won.

Win7

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 Win8

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 WinXP

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