Comodo Internet Security is good program. But it's not good to use.
Good to know that Your have just removed the dreadful Comodo Security (Free version) and installed AVG Anti-virus Free edition 2012 plus Malwarebytes Anti-Malware (Free version)
This is secure enough for home PC.
By the way, I think it's necessary to install a system optimization tool to maintain fast computer performance. I would like recommend you Cloud System Booster from cnet.
http://download.cnet....rm;productListing;pop
How do you think? It's depend on you. :)