An overly bright room will adversely affect the performance of a rear-projection television, and absolutely kill the performance of even the most expensive consumer front-projectors. Light from a brightly lit scene will spill into the room, bounce off any lightly colored or glossy walls, and then back onto the screen reducing the screens contrast. The result is less detail for you and your audience.

The solution is to use a darker color for your walls; something neutral like browns, dark tans, or black. Don't worry too much about painting your walls a darker color -- you're not going to end up with a cave. Whatever furniture you put into your theater, the lighting you use, and wall treatments you hang will help to balance out the room when it's finished. My family room is painted a nice caramel color, and the walls around and soffit above the projector screen are a nice chocolate brown. A tan carpet and recessed lighting shining down make the place look really comfortable. Wall papers are fine too. Just be sure to bring a sample home with you, tack it to the wall and shine a bright light on it at an angle. If it reflects any light, keep shopping.

I want to stress that you should stick with darker, neutral colors. Dark red or blue, for example, are a no-no because they will still shed some light. You'll end up with a slightly tinted red or blue screen image. Most onscreen colors won't be affected too much and you will get used to it after a while, but you can kiss pure white goodbye. Wasn't the point of spending a lot of money on a good projector to get a great image?