Martial arts in rubber turtle suits!

It's a children's movie, and rather dumb, and the exaggeratedly teenage dialog is bad, and the rubber turtle suits are also bad.  The story premise is beyond preposterous, but that was part of the charm of the original comic: it used the most absurd premise as a basis for action/adventure stories that took themselves completely seriously.  The original story was sort of a takeoff of Frank Miller's version of Daredevil... it was, you might say, a parody that never actually played for laughs.  The movie doesn't take itself nearly as seriously, being aimed quite a bit younger than the comic and explicitly looking for comedy (not very successfully), but occasionally some of the grim aspects still come through.

The movie's best strength, if you're over the age of eight or over the IQ of eighty, is the martial arts.  I heartily recommend that you do not do as I did and watch this in the same week that you see The Matrix Reloaded, because if you're expecting the fight sequences in the latter to be dramatically more intense and real and exciting and believable than in the turtle-suit movie, you're setting yourself up for disillusionment.  The movie's worst point is probably the rat puppet representing the turtles' teacher, Splinter.  The acting in the human roles is pretty far down the list, too.  The most embarrassing role is the largely extraneous Casey Jones, a human crime-fighter of semi-adequate abilities, who is thrown in to provide romantic interest for the turtles' human sidekick April O'Neil.