I haven't gamed much on an HD-TV, but just for watching normal 4:3 programming, our Panasonic HDTV has a mode called "Just," which does something fairly clever: it stretches the image out to fill the screen, but the center of the screen is 1:1 ratio. As you get closer to the left and right, it starts doubling pixels more. You get this slight wrap-around effect, and it's good for watching shows with the whole screen without everything looking squooshed.