There are several breakfasts you can choose from:
Minnies at Plaza Inn-
weekdays it's pretty laid back. lots of characters, most of the traditional characters (but no Mickey here). and often some surprise characters that are less traditional. there is a dancebreak that lasts about 3 minutes once an hour, but it is otherwise pretty laid back. it's just a laid back dance in your chairs or in the aisle with a character.
PCH Grill at Paradise Pier-
practically always empty. all traditional characters. this one has more activity as there are several activity moments, including a stitch surfing lesson and "stitch says", and a dancing lesson. so while there are less people in that big space, it's got more structured entertainment for sure. a live person narrates through the activities to help get guests excited to play.
Storytellers-
Non-traditional characters; koda, kenai, chip and dale, "woodland" creatures. this is more structured than Minnies, but much less structured than Paradise Pier. tends to be fairly empty for breakfast on weekdays.
Goofys-
sadly, never been there, except once, and it was abundantly full and crazy, but i'm sure fun was involved!
Ariels-
wasn't aware there was a breakfast here, so I have no idea.