When you want to best and most complete protection you should install an internet security program and not just an anti virus program.
I have tested several over the last 12 months.
Here is my top 3
3rd place Kaspersky Internet Security 2009
http://www.kaspersky.com/kaspersky_internet_security
2nd place Bitdefender Total Security 2009http://www.bitdefender.com/PRODUCT-2217-en--BitDefender-Internet-Security-2009.html
1st place ESET Smart Security http://www.eset.com/smartsecurity/
I purchased ESET and it is now protecting my computer.
As extra protection I advise you to install these 2 programs
Threatfire is an anti virus, that can be installed next to any other anti virus program on the same computer
http://www.threatfire.com/
This is a very good program, that completely runs in the background
http://www.comodo.com/boclean/boclean.html
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