Excerpted from http://www.techsupportalert.com/best_46_free_utilities.htm#3
A possible third choice is the AOL Anti Virus Shield [3]. This is a cut down version of the top rated Kaspersky AV and is being made available for free to all uses not just AOL members.
On first sight it seems like an unbeatable deal but it's not quite what it seems. First this really is a "lite" version. It lacks the important html and heuristics modules present in the full Kaspersky product so the protection afforded against hostile web sites is actually inferior to AVG and Avast!. Gone, too, is the ability to create rescue disks and to fully manage the quarantine area. The configuration options are also more limited.
Secondly the End User License Agreement is worrying. AOL basically reserves the right to spam you. I'm not aware of this actually happening but you need to be aware they have the right to do so.
By default AOL AVS installs the AOL search bar in Internet Explorer as part of the AVS install. If you don't want it, make sure you opt out during installation.
So on balance I'm cautious about recommending AOL AVS. If you can however, live with the limitations then you'll be rewarded with a first class scanner.