I'm using the Zenith 420 with the PC input on my Panny 42". In PC mode, Normal (4:3), Zoom, and Full are available. Zoom is designed to expand a 2.35:1 anamorphic movie picture to fill the whole screen. The 420 only allows changing *its* aspect ratio (most useful: 4:3 -> 16:9) in 480p mode (not 1080i or 720p).
Z