I have a problem with my computer freezing up.

I have a problem with my computer freezing up.

It runs very very sluggish in normal mode. When I click on "my
computer" it will not open up.

When I go into the windows task manager via Ctrl+Alt+Del. The
explorer.exe is 96% usage. But I have nothing else running that I am
aware of.

When I go into safe mode everything works okaY. I can open up "my
computer" all my folders etc.

Could this be a virus??? I can not access my memory stck in normal
mode to install the virus program. I can get it from the stick to the
desktop in safe mode, but then it will not let me install it in safe
mode. Therefore I can not run a virus check.

Can anyone help me?

Peter
Australia