I am using Windows 7 Operating System. I have currently installed Norton 360 in my computer. What are the other security softwares to be installed in addition with Norton 360?

Im a safe-surfer so I dont have a third party firewall, just the Windows and my router ones. Occasionally I run the free Malwarebytes' Anti-Malware from http://www.malwarebytes.org/ and SuperAntiSpyware, here http://www.superantispyware.com/

Norton has a "Pre Release Windows 7 Beta" download it's free. Been using it for 2 weeks now, no problems. It does say it expires in 7 days then 5 then 4 and then goes back to 7.