Haven't eaten at Tony's, the line/crowd at the entrance has always discouraged me, but The Plaza is a nice little spot. Simple menu, but it's good for lunch, mainly Sandwiches, but also Best burger in MK (Sorry Peco's Bill fans, but The Plaza's burger is on a whole other level!), great shakes and ice cream (the kitchen is attached to the ice cream parlor on the corner).
It offers a great view of the castle, and you might be lucky enough to be served by one of the most experienced staff at MK (there's a couple of waitresses there who have been around since opening day!) One of the chefs there is very accommodating if you have special needs, I remember on our last visit he came out of the kitchen and sat down with a family who had a child with several allergies so he could customize a great meal just for her. Added bonus the Main Street Mayor and other street character's also often visit during lunch.