one of the best ways to go is to always use a hardware firewall, such as produced by linksys, netgear, d-link, etc. if you want the big guns, get a watchguard unit ( www.cdw.com/watchguard )

using a personal software firewall in conjunction with a hardware firewall is definitely being on the safe side, but can mess with windows shares, and a few other apps.

the best thing to do, no matter which antivirus prog you get, is to keep it updated. Don't just assume that the installed program will find all viruses from now until the end of time. Every day new viruses come out, so every day the AV folks have to come up with new definitions. If you're not updated, you only protected against the viruses that were out when your AV was originally written.

hope this helps -skurit