There's a good amount of character interaction time with all but Santa Goofy stopping by the table multiple times over the course of dinner. If you're seated in the "front" (by the windows) space is a little tight as far as getting photos with the characters... it's a little more spacious in the center area of the restaurant. There are no character autographs during the dinner, you'll be given a small Holiday Card that's been pre-signed by all the characters.
Hollywood and Vine is not really a quick place to eat though. The wait past check-in always seem to be a good 15-miuntes, no matter if you check-in early, late, or right on time. Guests seem to linger here more than at other buffets. The "Minnie's Holiday Dine" is no different. So tag on another 15 minutes to however long you plan on eating!
I've always found the food to be quite good at Hollywood and Vine, but as cincystamper (above) mentioned, that's "for a buffet". It's not made to order, multi-process culinary… so as long as you go in expecting American standard buffet fare… you'll be happy with the food. If you're specifically asking how Minnie's Holiday Dine compares with Hollywood and Vine's "normal" dinner (which they aren't doing anymore)… it's about the same. The changes have been minor. Instead of Corn Spoon Bread, there's Cornbread Stuffing… instead of Citrus BBQ Chicken, there's Apricot Roasted Pork. It's all going to come down to personal taste. (The pasta station mentioned above is only available for lunch.) The desserts are all Holiday themed, which was cool, but all fall into the mini-tart, mini-cupcake, classification. There are no "keep warm" type of desserts on the menu.
There's a ton of photos for Minnie's Holiday Dine here…
http://goo.gl/gOrUHp