We were married in Disney in 2004,,we had a very small intimate wedding, (only 12 people including ourselves). We treated everyone to the Spirit of Aloha Dinner show after the wedding and had a great time. The night we were there the food was hot,,tasty ,,as I remember it and kept on flowing, and the service was great,,we absolutely loved our server! Of course maybe we were there on a good night and lucked out with our server,,but all of our guests enjoyed them selves and raved about it after. We were sure to mention that it was our wedding dinner when we booked the PS,,so we had seats upfront, we had our first dance there and were treated very special. Also,,when you first walk in,,you can have your picture taken out front,,the photographer took one of my new Hubby and me and then squeezed all of our guests in for another picture,,which was fun. The photo's cost a fortune,,but we bought them all anyway because we didn't bring a photographer. (which you actually aren't supposed to bring a "professional" photographer anyway,,but I think we would have been able to bring one and just have him use a more normal camera,,and not disrupt the show because you can have video and cameras inside.) Anyway,,sorry I got off topic,,but we did have a good time and wouldn't have changed a thing. *smiles*.
The only thing I would be worried about would be if your dinner party was very large,,it may be hard to have them seat you all together,,I don't know if they would let you rent out the whole place but for a smaller party it was fun.
Good luck with the planning and Congratulations