i had the same problem and just figured it out. When you mark a video (i had several videos that i converted that ended up in the 'movies' section as you) as a music video, it disappears form the movies list and is automatically transferred to the music list (not a playlist, just music). You can distinguish it from regualr songs because in the name field, there is a little tv icon there. i'm still trying to figure out where my photos are...and how to add them wihtout "sync"ing them...