Love Malware Bytes!
One piece of security software I have been playing with is a tool called Sandboxie at
http://www.sandboxie.com/.
I happened across it recently when looking for ways to isolate software from a system. If it does what it claims, it a makes a copy of critical files needed for IE or FF into a isolated area. Malicious software (virus/malware) cannot write to your real data to make a permanent change and infect your system.
It is free for personal use. The only caveat is when you start IE in a sandbox it pauses for 5 seconds to remind you it is free
