Antivirus program??

Anybody have a link for a good antivirus program?I downloaded AVG antivirus i don't know what the hell was screwed up with that but after i downloaded it and ran it everything froze :!: Wouldn't do anything so i shut down and started it back up and was only on my desktop for a few seconds and it rebooted itself :!: It did this like 3 times until i uninstalled the program now it seems to be working fine again.So watcha got :?: