Set the system up right, and you won't want it to.
J/K.
If it were me, just by going off of the room layout, I'd stick with 5.1. The center channel will help with dialogue, and you should be able to get the two front speakers on either side of the TV (right?). One of the rear speakers would go in the corner next to the bed, and the other rear could go somewhere near the other side of the bed. The exact placement won't be critical because of the Audyssey auto calibration.
As for mounting the speakers - are you not allowed to make holes as long as you fix them? I know that when I was in a dorm, we weren't supposed to make any holes, but as long as we fixed them up so that you couldn't tell, we never got in trouble for it.