I'm not sure if you are looking to rent points from a member, or book through WDW CRO (you can book villas as if a regular hotel room), but, as a member who was looking for a 2 BR for 5 people in Sept, Member Services (for
DVC members to book rooms) kept trying to put me in a 1 BR at the BWV, saying 5 people could be in a room. Knowing that most 1 BR only have 1 King bed and 1 Queen sleeper sofa, I didn't want anyone to have to sleep on the floor, so I turned down that offer. The exception would be AKV. Some 1 BR will have a sleeper chair to allow 5 adults (I'm not sure if these are in the current rooms or will only be in the new Kidani Village which will open May 2009). Apparently the new DVC policy is to allow 5 people in a 1 BR, but not provide linens for the 5th.
As for the dining plan, if you book as a regular resort room through CRO (or any
travel agency), you can book a package with the Dining Plan. If you rent from a member (which will save money, but the member has to be your contact with member services--they will not talk with a non-member), you can have them add the dining plan for you. You will need to purchase park passes separately.
Good luck!