So if my set does 480p or 1080i, what should my X-Box settings be at?
480p on or off
720 on or off
1080i on or off

Beau

I saw this model in Tokyo and it had 4 D4 inputs.So I think it's 1080i.D4 in Japan means 1080i ,so the image should be very good
http://www.image-acquire.com/panason..._tc_14la2.html

Here is the Panasonic Japan link
http://panasonic.jp/viera/px20/db/picture.html

I would go with:

480p on
720p off
1080i on

If your set converts 720p to 1080i, turn 720p on too.