Hi Cathy,
First, the 2011 Disney Dining Plan has different plan types such as Deluxe Dining, Standard and Quick Service. It sounds like you may have the Quick Service Plan.
This plan still offers 2 snack credits per day in 2011, however guests in 2012 will only receive one snack credit per day. Since you are visiting this December, if you have the
Quick Service Plan, your family will still enjoy 2 snack credits per person per day.
Now, let's move on to
Free Dining. The current offer is good for check ins December 11-16. You will need to call 407-W-DISNEY and ask for the offer to be applied to your current reservation. It is subject to availability and may not be available for all dates, so I would do this right away.
Let us know if you are still unclear about some of the details. But, please, first call to see if Free Dining is available for your dates!
Best wishes for a wonderful vacation. December is such a festive time of year at WDW!