Stage Lighting And Effects Equipment

I was watching a movie on my computer. The movie was really dark so I say "hey, how about I turn up the brightness?"SO I go to do so. But the movie was playing on full screen, the MENU button did not take. So I pressed the AUTO button. That's where it started. SO as soon as I pushed it, it went off center. THEN I pressed it again obviously assuming that it would reverse its effect. It didn't it made it worse. AND following my thought that it may realine itself eventsually I just held it down. THEN the monitor turned all sorts of colors in stripes up the screen , turning to a blank white. And keeps going. Ive unplugged numerous times.What do I do to get it back to normal? I've restarted it many times since turning off and back on and I saw the welcome microsoft screen so I know that's capable of displaying like normal. What do I do???????????
My mouse is not visable, nor is anything else except my rainbow patterned screen.