DVC member can book 3 of the dining plans, the Quick Service Plan, the Standard Plan and the Deluxe Plan. You do not need to purchase a park ticket through Disney to add the plan to a DVC reservation, but you will still need a pass to enter the parks, of course. Call Member Services at least 48 hours in advance to add a dining plan to your stay.
Special promotions, like Free Dining are not available to DVCers, unless they book through Disney and pay full price for the room like cash customers, promotional are not available for point stays.
If you are an Annual Passholder, you can purchase the Tables in Wonderland card (formerly Disney Dining Experience) for $75. This gives you a 20% discount at almost all Disney operated table service restaurants, including alcohol. The TIW card is also good at the food court in the value resorts, and counter service locations in Animal Kingdom park. The TIW is good for up to 10 people in your dining party, and is valid for about 13 months after purchase.