Is there an anti-virus that is good for dialup, and free?

I have tried AVG, Avast (both didn't work with my dialup). When I downloaded AVG it shut my computer down on its own without me even touching it. Avast just was really extremely slow trying to download the files needed. I had Avira but it stopped updating but I tried to reinstall and it did the same thing (I'm sure it's a glitch with that program).

Is there anything else free that is actually decent and free?

I am running Windows XP (I think Service Pack 2)

My dialup speed is usually 26.4

I'm not worried about my connection speed, it's fine. I've called the phone company and got information about it. I'm not complaining. It's cheaper than high speed and fits my budget. I'm just wanting a decent, non-spam, non-fake, anti-virus? Any suggestions?