The Fantasmic restaurants are normally Brown Derby (similar to the original Brown Derby), Mama Melrose (Italian food) and Hollywood & Vine (buffet). On rare occasions they offer different restaurants or lunch Fantasmic packages, but I don't think that's occurred for the past few years.
Two trips ago we were able to see Fantasmic, wander out slowly after many people had left, and head to Osborne Lights. I think when we went they actually showed Fantasmic at 7:00 AND listed MGM as closing at 7:00, too, but we were told by the CMs that we would have plenty of time to wander around, and they were right. We wouldn't have left the park until 8:30, I would think, and there were certainly others still there.
Hope this helps!