The Electric Umbrella - part of one of the Innovations buildings near the entrance (I just came so close to calling it communicore, LOL), is a great counter service that always has plenty of great seating, especailly in the upper levels. It's often overlooked at lunch time because people have made it deeper into the park by that point in the day. Plus, there is a great deal of glass walls to observe the park outside while you eat. The only other burgers/fries/chicken fast food in Epcot is at American Adventure clear across the park - which has similar fare and has a spacious dining room - but is very isolated from the rest of the park, unlike the Umbrella where you can watch the magic from the peace (relative peace) inside while you eat.
N.E.D.