For some of the larger places with extensive seating (Backlot Express HS, Seasons in EP, Cosmic Ray's MK, and others) we've had good luck in the 11:30-11:45 range. The registers are all manned for the lunch rush, making check out quicker, and most seating is still pretty open. I really hate getting a tray full of food then taking 10 minutes to find a seat when it's crowded. By 12 noon the real lines start. After 2 or 2:20pm is good too.