Firstly, this is a great TV set.
If the black borders are to the left and right of the picture, it means you are watching a 4:3 image on a 16:9 screen. Basically, it's the program you are watching - it has been sent to you in the older square format and since you have a widescreen TV which is far more rectangular you get the borders.
if the boarders appear to curve - it's because of the picture tube...the inside of it is not perfectly flat. The glass on these old CRT TV's is about an 3/4 inch thick and may appear to be perfectly flat on the outside but may have curves on the inside causing distortion in the image.
that's about as much help as I can offer without seeing it.
Jason
January 2008
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