Disney’s answer to “Shrek,” it turns out, wasn’t last summer’s animated adventure “Atlantis: The Lost Continent,” which proved a considerable disappointment, but this new co-production with Pixar Studios, the creative force behind the “Toy Story” pictures and “A Bug’s Life.” “Monsters, Inc.” doesn’t possess the wit and sharpness of its jolly green rival; it’s a simpler, softer, gentler, and frankly more juvenile piece, one that kids will doubtlessly take to more enthusiastically than adults. Nor does it match the overall quality of the previous Pixar productions But technically it looks great, and it has an easygoing, light-hearted charm not unlike that of Disney’s underrated 2000 entry, “The Emperor’s New Groove.”

It also shares with that film one of its stars–John Goodman, who here voices James P. Sullivan, a turquoise-and-purple ogre who’s the head scream-generator among the denizens of Monstropolis, a dimension to be found just behind the closet doors of all human children. Monstropolis gets its power supply from the energy of kids’ screams, which employees at Monsters, Inc., like Sulley gather by visiting the tykes at bedtime. Sulley is aided in his work by his factory-floor teammate Mike Wazowski (Billy Crystal), an ebullient, roundish green cyclops who’s also smitten with the firm’s secretary Celia (Jennifer Tilly). Unfortunately, Sulley also has a rival: the slithering, snakelike Randall Boggs (Steve Buscemi), who’s engaged in a secret plot that unhappily brings a live human child, Boo (Mary Gibbs) to Monstropolis–a catastrophe, since the inhabitants there are convinced that kids are toxic, and that their mere touch will destroy their world. Before long, however, Sulley and Mike have bonded with the giggly Boo, and must defend her against the machinations of Randall, the CDF (Childrens’ Defense Force) and the intervention of company boss Henry Waternoose (James Coburn). Many chases, close escapes, and last-minute rescues follow, but it won’t ruin things to note that all ends happily.

The premise of “Monsters, Inc.”–the idea of bogeymen being salaried employees of some corporation–isn’t entirely new; it served as the basis for a short film, for instance, that was shown some time ago on the SciFi Network’s anthology series “Exposure.” But here it’s elaborated in a fairly familiar Disney/Pixar way, complete with cute kid and a heroic comic duo composed of a lovable guy and his manic little pal. The storyline doesn’t go many places you wouldn’t expect, and the level of humor is pretty rudimentary, but the picture still works reasonably well. There are a couple of potential problems. One is the notion of kids being construed as inevitably toxic and of SWAT teams being brought in to fight the “infection” they pose. This will strike many as an unfortunate plot point at a time of terrorist threats and anthrax scares. Then there’s a turn toward the end when young Boo is captured and confronted with an ominous-looking scream-extraction machine, an episode that might frighten younger viewers. But for the most part the movie is fairly innocuous, mildly amusing fare.

The voice cast does reasonably well. Goodman is fine, more animated–if you’ll permit the pun–than he was in “Groove,” even if putting him into cartoon form seems paradoxically to reduce his size and energy. Crystal gives Mike his all, and he makes a good foil for Sulley, although he doesn’t match the effect his buddy Robin Williams achieved in “Aladdin.” Buscemi, surprisingly, makes a rather pallid villain; he’s scarier–and funnier–in his original form. The rest of the performers are fine if unexceptional.

“Monsters, Inc.” does include one in-joke reference that will sail over children’s heads and probably elude most adult viewers too, but will give a good laugh to genre cognoscenti. That’s the name attached to a restaurant that Mike and his sweetheart Celia visit. It’s called Harryhausen’s. Given Ray’s pioneering efforts to bring a remarkable range of creatures to the screen–though not quite as many as are on display here (understandable in view of the technical limitations he was working under)–it’s a fitting tribute. Still, the most enjoyable part of the picture comes at the very beginning. No, I’m not talking about the “Star Wars: Episode II” trailer that’s being shown along with it, but a wordless short called “For the Birds” that precedes the feature, which offers a sly take on an encounter between a flock of chattering sparrows and a single gangly interloper. It would be impossible for any full-length work to sustain, over an hour and a half, the verve and sheer exuberance of a brief piece like this one, and “Monsters” doesn’t manage the feat. But despite some flaws, for the most part it offers a genial, family-friendly ninety minutes’ worth of amusement.