Food will not be a problem whatsoever!
There are lots of options even for the picky person. You always have the pizza, hamburgers, hotdogs, tacos, chicken fingers and fries on Deck 9. The buffets have many choices with an adult side and child side.
Even in the restaurants you can choose whatever you want and since your servers will be with you the entire time they will get to know your tastes. By the third night our server would bring us our drinks without even asking. One server was working in the buffet at lunch and joked with my husband about his "Corona with a lemon" needs that he always had with dinner.
Even with an entre at the restaurants, you can change things around. So if they have mashed potates and you would rather have fries, no problem. If you want the dish minus the mushrooms, no problem. Each menu also has roasted chicken, steak or salmon every night for an option. You could also order from the kids menu if you like something there.
To answer your questions: the pizza is ok (not the best but not terrible). Room service is good as well with many simple options such as burgers, etc.
Either way, the food is amazing!