Norton's antivirus product versus the free Yahoo antivirus product?

I'm pretty sure that Yahoo uses McAfee, I don't know of any AV software being developed by Yahoo. At any rate, I found both McAfee and Norton lacking. As for a free product, probably the best one out there is AVG Free, when used in combination with a good firewall such as Zone Alarm, it's pretty good. For the ultimate in protection, I'd go for Panda Platinum (or I think now it's called Panda Internet Security). It's about 70 or 80 bucks a year for up to 3 computers, gives you not only AV protection but also protection against Spyware, Tracking Cookies, dialers, spam, everything. The feature that I like best about it though, is the Parental Filter, so I can keep all the scum away from my kids. You can get a free 30 day trial from Panda. Oh and stay away from that Microsoft Garbage, I tried it and it allowed SEVERAL popup generators to be installed on my system. Of course, I didn't realize it because it was stopping the pop-ups from showing up, but one day I was trying to run a game on my system and it was going so S>L>O>W>> that I took a look at the process monitor, when I realized I had about 10 pop-up generators running in the background eating up my CPU cycles.