Computer keeps freezing

Computer is still freezing. It happens when I open the internet or go into my folders. Everything opens fine but when i click on a folder or click on the scroll down bar to select a website when on the net it freezes. Then the 'Not Responding' msg appears. this lasts for approx 30seconds or so and then runs fine untill the next freeze. Was originally happening all the time but has since slowed down in frequency. It is still doing the this even after our last scan. Whats next ???

Is there more that I can do to solve this freezing problem???

Hello.
I see Norton is installed, Norton is pretty heavy on the systems resources, but if you've paid for it, you might as well get your use out of it and keep it, then switch when the subscription runs out.

Whats the best anti virus program to get???

I would recommend Avira.

1) Antivir PersonalEditionClassic
-Free anti-virus software for Windows.
-Detects and removes more than 50,000 viruses. Free support.

It is strongly recommended that you run only one antivirus program at a time. Having more than one antivirus program active in memory uses additional resources and can result in program conflicts and false virus alerts.

is there nothing else that i can do to stop the computer freezing???