The figures you mentioned are all resolutions. What Panasonic is this? If it were an EDTV (like the early plasmas), the native resolution will be 480p even though it can probably accept (and downscale) 720p and 1080i. A true HDTV (which is what I suspect you have) will accept both 720p and 1080i and if it's really new may also take 1080p, although it will take those resolutions and re-scale to the native resolution. That is where it gets a bit trickier - we need to find out what the native resolution is. The specs for the TV should include that. Typically, the best resolution setting will be the closest to the TV's native resolution.