If you want something that works well I have to agree about Malwarebytes free.
If cleaning up after an infection, the Superantispyware also.
Ccleaner is great for removing temp files (possible infections reside there)
and it removes the files that are left on your computer after logging in to banks or other such institutions. (A good thing)
As far as AV software, we use and recommend Comodo Internet Security with firewall.
This is our main business. (Computers)
