Modelling for games are a lot different than modelling for rendering/movies. They are two different lines of profession.

Your walls look fine. But you see these curtains and the legs of the table? Too much polygons? As you begin to populate room with more props, these just won't do. Amounts of polygons you can use is limited. You need to reach to a quality with as less polygons as possible. You may need to add some details by texture and alot with bump maps.