I exported out the 720 footage in SD and of course you have the 4:3 footage with no black bars. Then I exported it out for the heck of it to 1280 to see how it looked and everything is of course a bit larger, but you have the black bands on the sides.
Now this footage will be put on a DVD to be projected in a theater. Of course I need it to look the best. Problem is I cannot tell personally if any muddying of the picture had occured by exporting out to a larger size than what it was shot in, and if the black bars are more of an overall distraction than anything.
Also, i will have films from other people as well on this DVD. I am new to DVD authoring. I'm sure there will be a mix of formats. How exactly should i go about this whole thing?
DVD is only 720 x 480 NTSC or 720 x 576 PAL. Nothing else.
There are a couple of options here, too: 4:3 and 16:9. You can mix them on a DVD by setting the aspect ratio of each Timeline in Encore according to the source material. After that, it's up to the DVD player to display the correct aspect ratio on playout.