Yes, The Peacock Inn and elements offer the best dining in Princeton. While the food at both is superb, the cuisine styles are very different. The cuisine at The Peacock via Chef Manuel Perez is Contemporary American with definite French leanings, while at elements, Chef Scott Anderson cooks in his own very personal, eclectic style. They also have very different ambiance. The Peacock's the dining rooms (there are several) are elegant, and the nicely-spaced tables have cloths; at elements, the decor is distinctly modern and the feel is more casual, i.e., place mats instead of tablecloths. Both have stellar service.
The Peacock Inn photos here: http://www.flickr.com/photos/11863391@N03/sets/72157627349905090/
elements photos here: http://www.flickr.com/photos/11863391@N03/sets/72157621104415134/
This thread is a great reminder that we need to get back to both places - very soon!
A couple other bits of info for the OP:
-- The Peacock Inn has recently gone to a $58 3-course prix fixe dinner menu with $ supplements for a few items - if that makes a difference in one's dining decision.
--- The lounge at the Peacock is a comfortable place to have a pre or post dinner cocktail. Elements has a rather small bar tucked adjacent to a stairway and is less conducive to a leisurely gathering prior to dinner.
-- If time doesn't allow for a dinner at the chef's table at elements, consider it for the future. 9+ courses of dining excellence!