There are very few character lunches and they are all inside theme parks.
MK: Crystal Palace, CRT
Epcot: Akershus
DHS: Hollywood & Vine
None at AK
Note: For the past few years, during free dining in August/September, Chef Mickey's has served a character lunch. Hasn't been announced yet for this year though.
During our last trip, we did our first character meal - CP. It was perfect for our day/location. We did a quick breakfast at our resort, we spent the morning at the MK. We had a late lunch at the CP then watched the parade. After the parade, we did a few more rides then spent the evening at our resort and snacked.
We have done CP for dinner, but this was our first experience for lunch. It worked really well in our schedule and our DS5 still loves the Pooh characters.