When I choose a photo to replace the background photo in a widescreen DVD menu, it does not fill the entire background (black bars around the image). When I adjust the dimensions of the photo to make it fit, the photo, within final produced DVD menu, possesses noise and its quality is degraded a bit.

Question: What dimension should my photo possess when inserting it into a widescreen DVD menu? I am comfortably versed in Photoshop and Photoshop Elements. Are there any settings I can apply during a photo edit that will be helpful to me?

Thank you!
Di