Too many security programs?

Uh, well, I'm in a bit of a dilemma right now. I have a few anti virus programs, but I'm not sure if it's be too much. Currently I have Malwarebytes Anti Malware, Avast Pro Antivirus 5.0 and Spyware Doctor. I was actually planning on using BitDefender Total Security 2011 as well, but I'm not sure if that's a very good idea. Too much? Should I replace some, or perhaps remove a couple? All are registered except Malwarebytes and Spyware Doctor.

Hi Again
There is no "best", but what most members use for full protection is Security Essetntials, Malwarebytes and the Windows Firewall.
Corrine of this Forum, as well as myself use WinPatrol. Make a System Restore point and then download it. YOu can remove with the SR point if you do not like it.
WinPatrol makes a picture of your HD, if anything is downloaded it warns you and gives you the option to remove
Nothing else is needed or should be used. This is total protection
The rule of thumb is only one antivirus and one malware protection should be giving real time protection.