1. Yes you can lay them down. I laid mine down (for seconds because I needed to.) I'm not really sure I would risk it for the price of a plamsa, I have NO IDEA what longer periods could do to the set.
2. Most sets remember the stretch mode that they are on by input, which might be whats going on. However, your instance sounds more like you need to set your cable or satellite box to 16:9. Its probably on 4:3. Go into your menu settings on your box, not your tv, and change the HDTV out (RGB or component) to 16:9. Best I can say without knowing what you are using.
Question 1. Can I lay the screen flat for short periods without causing damage? The original packaging came with tilt indicators but there are no insructions regarding laying it flat (face up)on a table, for example, while hanging a new wall mount.
Question 2. When using the supplied RGB cable the screen shrinks for all channels - regular, digital and HD. When using the S-Video cable the picture fills the display with no loss of quality. What causes this?

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