Shows Black Screen When Starts

I was messing around with the settings trying to get a more clear pricutre, and now the desktop doesn't show any icons, no menu bar, and the background is partially cut out all around (like it's stretched to the original picture size). When I use ctrl alt delete the tv just goes black.The main problem is I can't use the main screen to adjust anything because my friend cracked it bad enough to where I can't make anything out.I have no problems using my friend's 40" tv, so I tried adjusting the resolution to a smaller size, but when I plug it back into the smaller tv it still doesn't work.I think this started happening when I changed some stuff in Asus Utilities Extended Desktop, but disabling that doesn't work.