We're heading down Dec. 11-16 this year with a similar party. Six adults and a 9, 5, and 2 yo. I've called for ressies already, and here's what we have:
12/11 - Hollywood and Vine in DHS
12/12 - Cape May Cafe in the Beach Club Resort
12/13 - Garden Grill at the Land in EPCOT
12/14 - Princess Breakfast at the Akershus, and late lunch at Restaurant Marrakesh
12/15 - Boma at AKL
I kept with mostly family-style and buffets, as we have a spectrum of eaters, from the picky, to the bland-food loving, to the super adventuous (Me, of course). My DH and I are doing most of the organizing for this trip, as his parents and sister with her family are rookies.
I do have most of our tables together, although I believe that Cape May and H&V we did get split. I've had that happen before, and ended up getting a big table when we got to the restaurant.
The best thing I can recommend is that you call NOW!!!!!! for reservations. You'll be better able to get times and places you want.
Happy eating!