Binding Menu to Controller?

Just wondering if this is even possible, because whenever I press B to go back up a level on the 360 controller while on the File Select screen, it asks to delete the file (assuming people use Backspace to go back up one level, but of course Escape is the key to do so without risking file deletion). Also, currently bound Pause to Start, of course, but I really want the menu more than just a generic pause.
If it currently isn't possible to do so, please make this a request for 2.1. Thanks.