ok, thanks for clearing that up.Quote from Aisone:
The realtime version of malwarebytes is the premium paid subscription. It's definitely not recommended to have multiple realtime antivirus programs going, as it can be a real drain on the system and cause conflicts. You'll be fine with microsoft security essentials for realtime, and malwarebytes and spybot for interval scanning or if the computer starts acting strange and chippy. A security essentials scan should also be run during this case.
I don't run manual scans very often since I haven't had a virus for >5 years. I use firefox with the noscript extension for browsing, and that minimizes a lot of risks that aren't as easily prevented using internet explorer.
I just intalled firefox today
what is the noscript extension? as it is now I have all the defaults