We had a character breakfast at La Bamba -- it was worth it for us since my daughter is the world's biggest Dora fan. Seeing Spongebob, Squidward, Woody Woodpecker and the Minions (from Despicable Me) were just bonuses.
The Dora meet & greet twice daily in the parks lasts about 15 minutes, so be sure to be there early/on time for it. Dora, Diego, Boots & Baby Jaguar come out in the "treehouse" float used for the evening parade, do a couple of songs and then quick meet & greets. If you're fast, you can meet all of them during one session -- but don't dawdle or you'll run out of time.