I recently bought a 55'' LED HD TV. Not all of Comcast's channels are in HD, and my GF loves watching the movie channels like HBO and Stars, which are mostly in standard definition, which means the TV screen looks something like this when you watch it: I'm concerned about the black borders causing screen burning. I would say about 2/5 of what she watches is like this (I only watch stuff in HD if I have the remote). When ever I come in the room and watch it with her, I always try to zoom in so the image fills the screen, but she usually complains that the image is now blurry. Is this something that I should be concerned about (and therefore lay down the law with her), or am I just being overly cautious with the new TV?