Mama Melrose is on the
DDP, you can even get the Fantasmic Dining Package with the DDP if you'd like.
Their Italian isn't the best, think Olive Garden without the breadsticks or salad, but their Steak Gorgonzola is great!
Hollywood Brown Derby is on the DDP, also with the Fantasmic Dining Package available. DDP Credit wise though it's a 2 Credit and most have said it's not worth 2 Credits (opting to pay OOP)
50's Prime Time has OK to bad food (In my experience), but has a wonderful fun atmosphere, no Fantasmic Dining Package.
Hollywood in Vine gets very mixed reviews, I've seen more negative than positive. It's a buffet, the food is good to horrible and cold. I've heard it can get really messy and the service is ok to bad.