The way that the doors and windows are positioned means that is has to be in the corner, with a chair in the opposite corner and a couch on each adjacent wall. How should I set up my 5.1 surround sound system?
that depends on where you plan on sitting when listening to it.
the center speaker goes under or above the TV
left and right go to the sides
rear speakers go to either side of the sitting area
if you put the left and right as far away as possible from each other you increase the size of the sweet spot where it sounds balanced.
(if you have a long skinny room)