Not sure where I got the AVG from.In MSE turn off Anti-Malware or Spyware whatever it is called to see if it makes any difference.If no difference turn it back on.
When it is not responding try Task Manager to see what is using up most of the CPU under processes.If nothing running System Idle process should be showing about 97% which is normal.Anything else using up a lot of the CPU let us know what.
Go into Device manager and see if there are any yellow exclamation marks beside any of the drivers.
Have you had any other Anti-Virus programs that you have removed lately.If so what.
If no joy with MalwareBytes download and Run Hitmanpro that only takes 5-10 minutes to finish it's scan.If it finds any problems you just have to activate the free license which lasts for 30 days and then it will remove anything that it finds.
Got a feeling that you have an unsigned driver which Microsoft reacts badly to so mind and have a look in device manager.
You could try typing sfc /scannow into command prompt and then clicking on the enter button on the keyboard.See if that finds and fixes any problems.
Are you using Windows Firewall or another.If another which one.
Who is your ISP and are you connected by ethernet or wireless.I/E9 or another.
when it starts not responding i carnt do anything with the computer other than hold the off/on button until it goes off firefox goes unresponsive alot aswell dont know wether thats got anything to do with it.theres 2 yello triangles in the portable devices one says I:\ and the other says WPD file system volume driver dont know wether that will help you guys. virgin media is my internet provider.i have just restarted my computer and all thats in the task bar thing is my avg and safely remove hardware icon cos ive got a external HD plugged in.in task manager my processes are 50 the CPU usage is flickering from 0% to 24% and physical memory usage is 10%.in the processes tab theres atieclxx.exe,avgtray,csrss,dwm.exe,explorer.exe,hpqphotocrm,sidebar.exe,taskhost,taskmanager,winlogon all showing up as running.but the applications tab nothing is running