I'd say the NWO from its inception through the year 1997 is the right call. Those members would include: Hogan, Hall, Nash, Giant, DiBiase, Syxx, Hennig, Bagwell, Konnan, Norton, Savage, Vincent, Elizabeth, Masa Chono, Muta, Big Bubba Rogers.
The NWO was the hottest thing in wrestling through that time so I'd say that the members of the stable from that period on would be the best ones to induct, but then we're splitting hairs.
I think the NWO Wolfpac and NWO of the WWE should be included. The fact that a stable had that kind of longevity over two companies is impressive.
If we induct the Horsemen are we not going to induct certain members like Paul Roma or Steve McMichael? Its not the induction of the particular members IMO its the stable itself, thus I feel all members with the exception of Chris Benoit should be included.