We usually get DDP, but I thought I remember reading that for 2016 that the Deluxe Disney Dining Plan does include an appetizer. Perhaps someone that gets the Deluxe will know.
The regular Disney Dining Plan included an appetizer, entree, dessert, drink, tax and tip. That was quite a few years ago. The appetizer and tip have been removed. For 2016 at many locations you can substitute a soup or salad for the dessert if such is available at the restaurant you're dining at. Have heard QS restaurants will substitute a snack for the dessert.