I second the Wave for really great salads and nice, portioned nicely ( NOT huge) meals.
Love their organic teas.
Their desserts come in little cups like 2 bites each so it's a treat- not a huge serving.
I have found that most table services will be more than happy to help you modify your meals to be a bit more healthy.
Fruit, fruit cups, are available at all 4 parks and DTD, carrot and celery packs are available too. Counter services almost all have salads. you can ask for dressing on the side. ( except in China- they kinda fuss at you
As far as kids meals go almost all table services have a healthy choice menu-
Example:50's prime time has grilled fish, rice pilaf and yoghurt parfaits
Grilled chicken strips, pasta and veggies, fresh fruit
Mama Melroses has grilled fish
Tutto Italia has griiled chicken on their menu for kids
Tonys at MK has grilled fish or whole wheat pasta primavera
At tables services ask to speak to a chef. Note on your ADR you have diet needs. There have been many times I have been made a meal that isn't on the menu at a table service
Counter services are a bit more tricky but you can ask for modifications on meals. you need to ask for a manager-I mean they can't change up a hamburger or hot dog

but some have salads
Contacting the special diets team can be helpful when having a food allergy or diet issue. they can assist anyone in finding places that will help you with meals.