We went with a family of six :) We only had one room, two double beds, a trundle and pack and play. We were only in the room to sleep so the lack of space was ok.
I checked a bag that was full of snacks and breakfast. (i also packed water bottles) I had packs of the small cereal boxes with a plastic bowl and spoon per person. We would clean them out and use them each morning. (we only had to buy milk and oj) We had the meal plan for lunch and dinner. It was very worth it! You get one sit down, one counter meal and i think a snack or two per day.
We payed about $4200 or $4600 for the 6 of us.... i cant remember. That was for 7 days. That included the airfare, hotel (in disney called port orleans riverside), dining plan, parks....everything. We did 5 park days. The park hopper package was a really good deal. This was in 2006, so a few things may have changed.
There was a website that you could book the whole plan. Go disney, i think? I am so sorry i can remember. I was so proud of myself for going and having a blast on what i think was a tiny budget :)
I hope you have a wonderful time!!