tony, the difference between SD and
HD is like night and day. All our affiliates send out 1080i and it looks great. Richer colors, higher cleaner quality, sharper details. SD looks good too, but its more blurry, more pixelation, less bandwith.
your TV should have an
HD tuner, and I *think* there are some boxes with
HDMI but I haven't seen any around here.
HDMI is the highest quality port.