Windows 7 - Expert Qeustion?

I was on my pics and I turn my pictures default program to explorer, my mouse started flashing on and off, it showed every like 100 pics in task manager, and I won't let me change my default program or anything. What do I need to do? ALSO I AM REALLY GOOD AT COMPUTER BUT HAVE NO CLUE WHAT TO DO!
Update: ????
Update 2: @frankg will it restore everything
3 answers 3