Which Anti-Virus Program?

I have always used Norton Antivirus. I have also used McAfee too. I prefer to use Norton more though. I always upgrade with them every year for the newest definitions to protect my computer. I have heard of AVG. Is it good? Is it free?

I don't use antivirus or antispyware (always have to have a firewall) anymore; I just lock the kernel: http://invincible-windows.blogspot.com/ The last time I used antimalware, it was McAfee. I've yet to find another vendor whose anti-drive-by technology (few have this technology yet) works as well as McAfee's ScriptScan.

I use Symantic Anti-Virus. Works real good