IMHO either
Malwarebytes Anti-Malware or
SUPER AntiSpyware will do quite nicely. I've used both and think they're equally capable.
I also haven't found it necessary to have multiple realtime scanners running. Just get yourself a decent antivirus utility with realtime protection features (Avast, Avira, Microsoft Security Essentials. etc.) and use that as your primary defense along with the firewall built into Windows.
Also grab a free copy of
Secunia's PSI utility to keep up on application updates and security risks.
Keep Windows, your malware definitions, and your apps regularly updated - and run Malwarebytes or SUPER every so often (weekly or thereabouts) and you should
never have a problem unless you do something very silly.
This is all I run on most of my systems, and I have experienced only
one actual malware issue to date. And that was about four years ago.
Luck!
