Yes, you will need to inform the member you are renting the point from, so the member can call Member Services to add the plan to your ressie. You do not need to purchase any particular park ticket to qualify for the DVC version of the plan, like you do on a cash package.
You will pay for the dining plan when you check-in at your DVC resort.
Plan is $37.99 for adults and $10.9 kids (2006). $38.99 adults (2007)