Best decent, non-spam, non-fake, anti-virus?

Well, you don't like them.

AVG shut down your machine? Never heard of that.

But I will tell you this. Some of the updates are large files, and can take forever on dial-up, and in some cases, the connection may drop.

I don't know what to tell you. The three you mention are the best free at what they do, and always get good reviews.

Unless your machine is infected and hosed up with junk.