Using Gallery stored images for users to put on to drupal pages

I would like my users to be able to customize a header image for a page they are creating. I would like to know if I can allow them to see a gallery and pick a particular image that then the chosen image could then be placed into the header of their page. Or if that is not possible; is there a way to query the Gallery2 images available to populate a drop down list that would appear in a drupal form?