How to disable the back key?

For about a month or so, my tablet has been going through short periods where the back button, for lack of better descriptors, "presses itself" repeatedly. When this happens its difficult to do anything on my tablet because every app I open closes itself before I can do anything on it. Recently its been getting to the point that this is all that is going on. What happened exactly was I must have dropped it because I happened to notice a crack on the screen where the camera is on the black border, and then the soft keys didnt work at all. I installed "Button Savior" on it and everything was working fine again but now I have this issue, so I thought that maybe its the app, but when I disabled it it still happens. I figured I'd try this forum before I try to find somewhere to get it fixed.