Whevever i try and open My Computer, My Documents or Control Panel or anything to do with windows The screen goes blank for a few seconds the toolbar disapears for a few seconds then comes back on but still no My Computer etc.
Most likely something has hooked itself into the shell. First thing I would do is go to the Add/Remove Programs in the Control Panel and remove any free software "FreeWare" you might have. Next I would check for viruses with Stinger (*free*): http://vil.nai.com/vil/stinger - download Stinger and see if it finds anything. Also look for rogue spyware with AdAware Personal (*free*) from http://www.lavasoft.de
There's also a program called "Process Explorer" from SysInternals ( http://www.sysinternals.com/Utilities/ProcessExplorer.html )which could aid you in identifying whatever is causing your shell (explorer.exe) to crash/restart itself. When a "nasty" child process nests in explorer.exe you won't see it from the standard Windows Task Manager - this program shows you each thread that spawns in each parent process. From there you might be able to tell what is being called to eventually crash the shell so you can research its origin and purge it from your system.