The bars are not a part of your movie. When you show a 16:9 film on a "normal" television screen (which is 4:3, or 4 fields wide by 3 fields tall), the black bars are what the monitor shows because there is no picture information at the top and bottom. The monitor generally tries to show you all of the picture it's getting (notwitstanding any monitor overrides and special features). So it shrinks your movie down until the widest bit of it is on the screen, then fills in the rest with black.

If you show your 16:9 movie on a 16:9 screen (like a widescreen HDTV) the bars will not show up because the monitor fits the movie shape. In fact, if you don't adjust your picture, when you show a 4:3 TV show on a 16:9 monitor, you will get bars on the sides because the monitor is wider than the picture.

If you taped it in 16:9 and you export it 16:9 (or full frame), you will have your bars. But if you've already tried to do this, and it doesn't seem to be working, it's probably because you're watching the movie on the same system you cut it on, which should be configured for 16:9. Take the disc out, and put it into a DVD connected to a regular TV, and Viola!

And just as a point of information, most theatrical movies which are widescreen (anamorphic) are 2.40:1 and are shot with special lenses. 16:9 format works out to be 1.78:1, not as wide as "Widescreen" which is having it's 50th anniversary today. Happy birthday Cinemascope!