If you want 480P only, you will get the best picture from a CRT TV. They are big and bulky, but beautiful (and relatively cheap). I believe the biggest you can find these is around 34-36 inches. I have a 30 inch Samsung and love it.
Just make sure you get one advertised as EDTV (Enhanced Definition, or 480P).
Just make sure you get one advertised as EDTV (Enhanced Definition, or 480P).