You actually have a choice of 3 different character meals that you could do without having to enter the park - Goofy's Kitchen, Storytellers Cafe Critter Breakfast and Surf's Up with Mickey.
Goofy's Kitchen in the DLH has the largest buffet - tons of choices. The usual characters are Goofy, of course, Chip and Dale, and often times Baloo and Pluto, and others which could range from any of the Princesses, Minnie, Max, Captain Hook, the Genie, Alice and the Mad Hatter, Aladdin, Fairy Godmother, etc. There are usually anywhere from 5 to 8 characters in the restaurant at a time.
The Critter Breakfast in the GCH has a small buffet as well as menu orders. The characters you will find here are Chip and Dale, Koda and Kenai, often times Terk, Meeko and sometimes other woodsy/jungly characters. Usually no more than 4 or 5 characters are there at one time.
Surf's Up with Mickey in the PPH is the only meal where you will find Mickey. They serve a buffet (not as small as the Critter Breakfast but not as large as Goofy's). Characters besides Mickey include Stitch, Daisy Duck, sometimes Pluto or Goofy or Minnie, and maybe others I am forgetting.