The Crocodile Hunter, Steve Irwin, Mr. “Don’t try this at home!” makes a terrific, kid-friendly big-screen debut in “The Crocodile Hunter: Collision Course.” The movie surrounding him is as lame as a three-legged dingo. But Irwin, the open-faced, wide-eyed and heroic goofball naturalist, shines in a comedy that entertains as it teaches us about the killer critters Down Under.

Irwin, a staple of TV’s Animal Planet, runs his own animal-rescue service in Australia. His specialty is crocodiles, which he saves from poachers, irate property owners and the like, always by wrestling them into submission. With his American wife, Terri, he travels the wilds, grabbing deadly “Fierce” snakes (an actual species), whopping spiders, zany lizards and shows them to an eager TV audience.

His TV show director, John Stainton, must’ve seen “Ice Station Zebra” recently. That’s the movie he copies to put Stevo on the big screen. A satellite film canister crashes in the Outback. A croc eats it. Competing U.S. intelligence agencies want it.

And all Stevo wants to do is keep the croc from being shot by rancher Brozzie, played by Babe-the-pig’s farmer mom, Magda Szubanski.

Stainton wisely lets Stevo be Stevo here, shooting the Irwins in their own context as animal protectors, and in square TV aspect ratio. Steve talks to the camera, just as on his TV show. The screen widens whenever we wander off into CIA movie land, where over-dressed or tightly dressed (Kate Beahan) agents run hither and yon, tracking the croc with the billion dollar belly.

In the end, despite his sweetness, his wonderful do-gooder instincts and his sly educational value, we’re left with one conclusion Irwin’s a nut.