Rose,
Thanks for your question!
Yes, you can use
Disney Dining Plan credits on your departure day!
Basically, as you may know, you get a 'set' of credits for every night you are staying at the resort, dependent upon which of the plans you are using. For example, with the
standard Disney Dining Plan you would get 1 table service meal credit, 1 quick service meal credit, and 2 snack/beverage credits per night of your stay. But you can start using these on the day of your check in, all the way to the day that you check out. Even if you have already checked out, you can still use them right through the rest of that day.
On a personal note, when it comes to itinerary planning, what to do on a departure day is really tough. If you don't have enough time to dedicate to going to a park, lounging around the resort hotel can be very anti-climactic. What you are suggesting, a Character Breakfast, is an excellent way to extend the magic before leaving to head home.
If you write me back, I would be glad to recommend a few, based on personal preferences and where you are staying to minimize transportation woes. But until then I will tell you that a few of my favorite resort-based Character Breakfasts include
1900 Park Fare,
Chef Mickey's, and
'Ohana.
Have a Magical (and delicious) Vacation!