Of course the drawback to wide screen format (16:9) on a standard TV (4:3) screen is that the picture height is reduced and while you'll see everything that's in the original picture width, it can sometimes be rather tiny overall if you have a smaller 4:3 TV screen to begin with. This effect is quite pronounced with "How The West Was Won," since the original Cinerama screen was much wider than even with the 16:9 wide screen today. On my 27-inch 4:3 TV, the picture of "HTWWW" is so tiny it's hardly even enjoyable to watch. Some DVDs come with the 16:9 format on one side and 4:3 format on the other, and the label has to be printed in extremely fine print around the hub of the disc.
The 16:9 screen predominates in most new TV sets today, of course, and if the 4:3 format of a tape or DVD is viewed on such a screen the black bars will be at the sides instead of at the top and bottom.