Second Turtles hand's down in my opinion. It more closely followed the comics and well I just thought it was more awesome then the first silly turtles. The third turtles is a decent mix of the first and second, but for now it holds second place as far as Turtle cartoons go.
2003 Turtles. The '87 version was great, and I'm really enjoying the '12 series, but '03 TMNT was probably my favorite portrayal of the Turtles.
While the '12 incarnation of the Turtles is pretty good IMO, it just doesn't click with me like the original. I've never seen the '03 aside from Turtles Forever and it kinda made a mockery of the original which I wasn't that crazy about.
Turtles Forever wasn't technically part of the '03 series. Also, while I wasn't fond of how the '87 Turtles were portrayed in the movie, the writers did have a point. Compared to most other incarnations, the '87 Shredder was laughably incompetent. "Turtle Power" wouldn't stand up to the cold brutality of Utrom Shredder.
They did have a point but once it was made, it got to where it just felt like they were shoving it down the older fans' throats. Like, "Alright, we get it, the original was more lighthearted, now move it along."
Honestly, the old turtles will still remain to be the best through time. The turtles that came after it was alright. But with the most recent turtles... yeah... I would like to put a gun to my head now...
OK, this is "best TV show based on a comic book that's not DC or Marvel", not "best Teenage Mutant Ninja Turtles show". It depresses me that none of the other cool shows get any attention simply because people here won't shut up about the damn turtles. I mean, I'm pretty sure at least "The Walking Dead", "Cybersix" and "The Tick" are popular shows, so what the hay?
I second Rex's comment. Turtles are the best hands down. Tick, Sabrina the Teenage Witch, and Archies Weird Mysteries were good, but they are not the best.