Posted 18 February 2007 - 05:33 PM
Windows firewall only checks incoming packets; a fully featured firewall will check those as well as outgoing packets; the latter prevents malware from "calling home" if it ever gets on your hard drive.
I have used AVG for several years with great success. As long as an AV provides real-time protection, has frequent definition updates, and is fairly easy to use, you have many from which to choose. Since these are free, you can download, install, and update one of them at a time and see which you prefer.
Whereof one cannot speak, thereof one should be silent.