Pardon me for my ignorance on this , but sometimes I will accidentally do a 2 finger swipe on my magic mouse and an entire new desktop appears on my iMac. It is very annoying to me. I'lll be working on something and bump my magic mouse in the wrong manner and boom I'm on a new desktop. The screen swipes away left or right. I think this is called mission control, and is there a way to totally disable it? I would like to deactivate it if possible. Thanks