No offense to beatnik, but I would need more of an explanation on how to do this. I am no expert, just a hobbiest, but I would do it using a mask.
First, duplicate the text track so you have two identical tracks. Then on one of the tracks you need to use the chroma keyer and contrast to get the text all one color (ie: white) and the background just leave black. Now put the black/white video just above the original text video and click the mask button on the very left side of the lower track. Now you have a mask that exactly follows the text, and will allow only the text itself to show, while all the black is set to transparent. If you find that it actually does the opposite of this, go into the mask generator and click the 'invert' box.
Now, if you just put the picture or video you want to appear in the background in the third track down, it should accomplish your goal.

Have fun!

I tried that but it doesn't work.. I put the clip with the black background on the top track (and the main video on the bottom). Added an FX to the top track - Chroma Keyer - and used the eyedropper to set the color to black (0,0,

Played the video, and only the top track shows in the preview window.

I even made a still jpg image with a black background in Photoimpact and tried that on the top track, but no luck.

Steve

Perhaps I didn't fully understand the original post. I thought that he had an .avi
file of some text with a black background. In order to show the text over a movie
he has on the timeline he just has to plcae in the highest track and chromkey it to
black....and that's it?

The solution was simple: I uninstalled VV4, then reinstalled it, and everything works fine, as expected.

Used chroma key FX on top track, using the eyedropper to select "black" as the transparent color..

Thanks all,
Steve