I odn't know if you guys can help me but...

This just started last night. I was doing an icon and went to do brightness/contrast and when I click it, everything freezes. The close button is faded out and I can't click anything. If I go to the bottom on the task bar and right click to close there is no option. I end up having to do, Control + Alt + Delete. I've restarted my computer and that did fix it... please help?