2. Star Trek: The Original Series (IMDB: 8.4/Rotten: 80%)
I'm a bit shocked, but not surprised that Star Trek's first foray into television is only second on Shatner's list. A stellar science fiction show and one that did so much for the industry at large. It's a cultural touchstone and one that the series itself is still trying to replicate the success of today. While there have been dozens of shows, films, and books to come out of the franchise since the original 1966 series, none were as massive as the original. Maybe The Next Generation but even then, the original had a larger audience.
Still, Shatner was a core reason for the success of the show and the larger franchise. So there's a case to be made that it should be number one. Yet, so many others have come after him and contributed in large ways as well, and since the franchise has been going for nearly 60 years, but only about 30 with Shatner, it's hard to say the series couldn't have survived without him. As it clearly has.
Thus making his impact a bit less impressive than previously thought.
1. Boston Legal (IMDB: 8.5/Rotten: 86%)
While Boston Legal doesn't have the same cultural impact that Star Trek had, what it did have was arguably Shatner's finest acting role. While ratings, episodes, and cultural significance all matter, at the end of the day what matters most is Shatner's performances. He starred in Boston Legal in a way that caught many off guard. In his early 70s when the show came out, Shatner was every bit the dazzling charmer he's always been but even more so.
So it's not a surprise that the show has the scores it does. It's also not a surprise that Boston Legal, and not Star Trek or T.J. Hooker, is the show that Shatner was a star of longest.