That was one of the first things we did (my Dad helped some). Both my DVD players (Sony 5-disk and a Toshiba DVR/DVD burner) are set at 16:9.
On the same settings: 1. Episode 3, which is labelled as being anamorphic, filled the screen the best it could (had small bars top and bottom since its 2.35:1). 2. Back to the Future left no bars at all (has a 1.78:1 aspect ratio)