Generally not working

Whenever I load up a rom, the emulator goes full screen and stays black. My computer slows down a lot and I have to close it, getting an "end now" window, followed by one of those windows to report the problem.

After saving and closing Final Fantasy V, I tried to play another game (can't remember what. Pretty sure it was a GBA game.) I got the "(Not Responding)" deal and closed it. Trying FFIII for the DS, I get the same problem.

I've gone through every game in my library and gotten no different results. Been using No$GBA for quite a while and never had any problems. As far as I can tell, no other functions on my computer have affected and I didn't change anything in the thirty seconds between games or while I had FFV open to begin with.
This all happened last night. I shut down my computer since then and tried a few games just recently.

Any idea what's wrong?