slcred wrote:when I rent hd on demand movies they have a black box on the top and bottom
Sometimes in your tv settings you can change the view. Cinema, music, standard, hi contrast, stretch etc. additionally there can be 1080p or 780i etc. which can show the media larger or smaller.
read the manual for your tv first. When I had cable there was settings like I mentioned above in the set top box which could be changed.