So I am editing a music video. I want the there to be video playing where the black boarder (bars) usually would be. How would I go about changing the size of the video frame but without stretching the video itself (the objects in the video)?
In pan/crop, you right click on the image, and set the option to "Match Output Aspect". That should insure that there are no black bars even if the video itself must be cropped to reach that objective. I regularly do this since I shoot HD 1080i and p, but render to a DVD resolution. That also allows me to adjust which part of the HD image is displayed in the render so that I choose what I think is the best composition.