MK -
Crystal Palace - Doesn't matter-- We have done lunch and dinner. They are pretty much the same-- it is pretty during the day with the light shining in- we prefer lunch. We do not do breakfast--we do not like to lose park time and DD is not a morning person so rope drop is hard enough- we tried the pre-park opening breakfast once and it did not go well (even just a 1 hour time change is enough to make it not good for her).
Be Our Guest - Dinner. I've heard breakfast the food isn't worth the price. We have done lunch and it is fine, but it is basically a CS meal- you go through a line, pick your seats etc. Dinner it is a sit down meal, much less hectic because people are not wandering around looking for tables etc, and most importantly, the Beast is there for photos and meet and greet. We love BOG and were very sad last week when Hurricane Matthew made us lose our Friday ADR.
CRT- Doesn't matter. See the above in regard to Crystal Palace, with the exception that the light doesn't make that big a difference- it is just as pretty whether you go day or night. We have been both.
HS-
Hollywood & Vine --- Must you really do this one? The meal would depend on which characters. Disney Jr. is during the day. At night it is Minnie's seasonal dine- which means instead of the Disney Jr- you get Minnie, Mickey Goofy, Donald and Daisy in seasonal clothes. We ate there last week. The characters were absolutely adorable and our server was very nice, BUT it was one of the 2 worst meals we have ever had at Disney. We had to wait over 1/2 an hour for a table; the restaurant was filthy, the dessert was really good, but the rest of the food was near inedible- it was disgusting. We had to wait over an hour after we finished eating for all the characters to make it to us. Maybe we just hit a bad night- but while if the character costumes were really cute we might try it again- outside of that we would not eat there again.
Epcot -
Via Napoli - Never eaten there
Resort -
Ohana - Never eaten there
Chef Mickey's - this was our other worst meal. We went for dinner-- it was filthy and the food was in large part not good (although not as bad as H&V last week). That was a few years back though. I would say it depends on the rest of your schedule for the day. If you can do it without taking away from park time- then breakfast. If it is going to take away from park time- then I would do dinner.
In general, we like to do TS for lunch. We usually do a quick breakfast in the room (DH goes to CS and gets it and brings it up- or if we are staying CL which we have done a couple of times- breakfast here is where we feel that we make up the increased price). We don't go back to the resort for breaks, so a TS lunch gives us a nice rest and break and gets everyone geared up for the afternoon in the park. When DD was younger, dinner could be a little hard, because she would be getting tired at night and would be antsy at dinner. If we were out in the park and did CS for dinner, her adrenaline would keep her going and she would be fine- but if we sat her down at TS, she would crash or become very very fidgety.
FWIW, we had one of our best meals at H&V this past August. 
