The main suggestion for NYE dinner is "book early". You also might want to decide how you want to spend NYE. If it's over a nice dinner that's great. If it's in the parks, that's wonderful. However, it's hard to do both (unless you eat in a park restaurant). The parks will be packed and will usually cut off entry at some point.
CG, the obvious choice, generally runs a special event dinner with a price tag in the $300 pp and up range. They usually have some sort of casino event and I bet it's a good time, just be aware it is pricey.
GF has a dinner dance in the ballroom. Atlantic Dance at BW also usually has a big ticket event of some sort.