You don't say if you are looking for counter service or table service.
At Animal Kingdom for counter service we love Flame Tree Barbecue (we don't do pizza at Disney--they do not have good pizza but, then, Florida does not have good pizza); for table service it is definitley Yak & Yeti.
At the Studios for counter service we leave the park and go to one of the resorts and have our counter service there. We just don't like any of the counter service at the Studios. For table service, we always do Mama Melrose. Our second choice would be 50's Prime Time followed by Sci-Fi.