Our family did this over Easter break. We checked in at a podium at the Odessy at 7:15. Our reservations were for 7:30. You wait for a cast member to call your name and take you inside. You are seated at round tables with your group. You get a special pin to wear so when you go to view Illuminations they can identify you. There is a "character", Auntie Roz who asks if anyone has a birthday, anniv. or other special occasion. She and a DJ do a little show and get the kids invloved with storytelling and dancing. While this is going on, you can go to the buffet. We had fajitas, bratwurst, lazagne, sweet and sour chicken, rice, potatoes, salads, roast pork, a chicken dish... international dishes from about 5 countries. Can't remember it all! Don't know if it varies or not. Kids buffet had chicken fingers, mini hotdogs, mac and cheese and pb&j. Included drinks were sodas, tea. They offered beer and wine. These cost extra. Also, Minnie and Goofy come and meet everyone and you can have a group photo made with them. After dinner you are lead out to the viewing area in front of the gift shop that is at the beginning of world showcase. It is front and center for viewing the fireworks. This is where desserts are usually served. It was so cold the night we did it, we were served inside the Odessy. There was a fruit cup, strawberry cake, a chocolate mousse, a lemon cake..more but I don't remember them all! Also coffee and hot tea. We enjoyed this event. It was nice to escape the crowds and not have to stake out a spot for Illuminations!
Auntie Roz is kinda corny but it's geared toward families. Our kids enjoyed it and they are teens. They didn't mind watching the "little kids" have fun.
Hope this helps!