This isn't really the place for this question. It's not really related to game dev. However, I'll try to help.
Under the file menu is an option called Load Factory Settings. I'd try that. If you can't get to the file menu, in the top left of your screen shot, under the red close button, there's a little cube. Click that cube, then select the "Info" menu. That should allow you to access the file menu. Otherwise, instead of the "Info" menu, open the python console and enter the following:
Then, to save those settings so you don't have to reset to the defaults every time you start Blender. Go to File->Save User Settings. Or press Ctrl+U. This should save the factory default settings over your settings that went awry.