Seeking advice on what to install along with AVG free/Avast free

Hello! No problems at the present time, just wondering what you advise as far as keeping my computers clean. I have AVG 8.0 free version installed on three systems and Avast 4.8 free edition on another laptop. I am also running MalwareBytes scans on these computers. What other apps would the experts suggest that I add that won't interfere with the AVG and Avast? We use Mozilla as a browser (only use IE for one work site because I have to) and I've just installed some suggested add-ons of NoScript, Adblock Plus, and Flashblock.

Thanks in advance - Belahzur saved the day when Spyguard 2008 took over my husband's laptop. Y'all are the greatest!

That should be good enough protection.

Thanks for the feedback, Belahzur!

How about using another anti spyware such as SUPERAntiSpyware?

http://www.superantispyware.com/

I'll give this a try as well. It's my husband's two systems that are the biggest challenge as he sometimes forgets all instructions when it comes to opening emails. Thanks for the suggestion and the link!