yes, on the Fantasmic Dining Package at MM you get the full meal, no menu limitations. We just did this last Thursday (5/28)
There are a couple of appetizers on the menu that are listed as "for 2" like "calimari for 2" and the breads/dipping oil is also "for 2" -- if you choose those, you have to have two people order that (a single diner cannot order the "for 2" apps on the dining plan) There are some other choices that a single diner can order, including a salad or a bruschetta plate. Last week, DH & I got the calimari for 2: was wonderful, DD got the bruschetta: said it was just so-so, and BFF got a salad: said it was good.
Entrees are not limited at all, nor are desserts. We enjoyed the food, though the service is a little slow -- was the longest meal all week (just over 1.5 hours)