I have been on weight watchers for a long time and it's really not working too well for me

but I respect your determination to at least try to eat healthy during your vacation. Yay, you, way to go!!! I'm assuming you're talking about dinners, here?
At 'Ohana, avoid the bread, limit yourself to one wing and one spoon of noodles. Enjoy the salad and skewered meat. The dessert here is absolutely fantastic, but if you have a very small portion, you'll still be OK.
At Boma, avoid soups that are creamy and bread. Stick with the salads and the carved meats, and don't taste each dessert, pick one or two (they are small). They have great fruit and salads here, so fill up on those first so you're not starvng when you make your other choices.
Tusker House, same as Boma.
1900 Park fare: avoid the casseroles and limit desserts. Eat salad , fruit, strawberry soup (small amount, I think it might have sugar and cream added). Stay away from creamy salad dressings (of course, as with all other places). Carved meats in small quantites are fine.
Never been to Sci-Fi.
At Whispering Canyon, get a soft drink, not a shake. Do NOT order the skillet, instead, pick a regular sized entree, maybe the trout? Ask for it without butter or oil. The skillet is gross anyway! They have a fresh fruit dessert. It's a little boring, so make sure someone in your party gets a smores cheesecake and taste a bite or two.
Liberty Tree (dinner?). Just limit stuffing, potatoes and gravy. Enjoy the turkey breast and the ham. Ask if they can bring you veggies prepared without butter. Split a dessert between a few others.
Remember, it's not necessary to finish what is on your plate. Stay well hydrated so you don't misinterpret thirst as hunger (carry water and drink all day). Also, if you enjoy an alcoholic beverage, avoid the calorie-packed mixed drinks like margaritas and pina coladas. Those things are like 13 points each! You could probably have 3 bite-sized desserts instead, if you think about it. (Personally, I'd reather have the avocado margarita!) Choose one glass of wine or a simple martini.
Good luck!!