I used Norton for years and after it started to bog down my computer went to McAfee. Dumped McAfee after getting multiple false alerts and am now using Panda A/V and am totally happy. I agree with Steph3n on most of his points with the exception of a defragger. My six year old desktop would sometimes taking longer to boot than my 12 cup coffee maker to make a full pot of coffee. After a lot of research and speaking with computer techs at big box stores and the three local schools of higher education I bought RegCure by ParetoLogic® and my system is back to whiplash start-up speed ^ Two other options you may want to consider is the free version of Zone Alarm and check out the excellent freeware at Gibson Research (http://www.grc.com/intro.htm).