I would vote for O'Hana. If your kids don't want to participate in the games and fun, they can just stay at the table and watch. They keep doing it throughout the evening, so they can always watch for awhile, then get up and join in. Also, at O'Hana, you might luck out and get a table with a view of the castle. What better way to get you in the Disney spirit than that? Kona Cafe is great, but really more like a coffee shop in atmosphere. I love their menu and really enjoyed eating lunch there, but for dinner I think O'Hana has a better overall atmosphere. Also Disney restaurants are more than happy to accomodate your special dietary needs. Make sure you tell them when you make your ADR's, regardless of where, that you are a vegetarian. Then reiterate that to your server when you are seated and see what they can offer you.