At home we use the usual AVG and Zone Alarm firewall for the most part.

But my kid wanted to play an online game and something didn't work so we changed to Avast.

For an alternative firewall we can use Comodo.

-> But most of the protection is from simple rules like not using Internet Explorer unless there is no other choice, turning off email message previews, not opening any email that we didn't expect and so.

Also, no one I know caught the Antivirus 2008 or 2009 plague. But you see how many could get suckered into that if you read http://www.theregister.co.uk/2008/08/22/anatomy_of_a_hack/print.html

So there you go. Alternatives.
Bob