Moorestown NJ Area Diners?
The 2 most popular diners in the area would probably be Ponzio's (Rt. 70 and King's Highway) and the Silver Diner (Rt. 38 across from the Cherry Hill Mall). Both are what I would consider to be on the high end of the Diner spectrum. Sage Diner (Rt 73 south & Church Rd) is a decent middle of the road diner. There is also the New Golden Dawn Diner (570 Rt 38 East, just past the Rt 73 on-ramp) that is a typical NJ diner. There are also a couple of places on Main Street in Moorestown/Maple Shade that are actually closer to coffee shops than Diners, but might be what you are looking for. The first is called the Whitehouse (Main Street and Lenola Rd, across from McDonalds). The second is 2 blocks further up Main Street in Maple Shade called Maple Hill.
It's been a while since I've eaten at any of these Diners, so I can't give you any specifics on which one is best. The only Diner in the area I would tell you to avoid would be Olga's(Rt 70 & 73) in Cherry Hill. The original owners sold out years ago and it has steadily gone downhill since then.