The fact that a movie is good-natured doesn’t mean it’s good—a truism confirmed by Tom Hanks’s first directorial effort since “That Thing You Do” back in 1996. Hanks also produced “Larry Crowne” as well as co-writing it and taking the title role. His investment in it only goes to prove another old saw, because though in the picture Larry is a nice guy who finishes on top, in the real world nice guys like Hanks end up decisively out of the running. This is a comedy-drama hat isn’t just old-fashioned, it’s positively musty. It may be set in the present, but feels like an antique—not a valuable one, though.

That’s not entirely Hanks’s fault, however. His collaborator on the script was Nia Vardalos, who had an unaccountable smash with “My Big Fat Greek Wedding” (which Hanks helped get made) but has since produced nothing but abysmal low-budget romantic comedies. “Crowne” bears her imprint all too clearly.

Larry is a middle-aged divorced guy who spent twenty years as a Navy cook and now relishes his job as a clerk in a WalMart-style everything store. He’s shocked one morning when he’s let go—in a scene presumably meant to feed into the current economic climate—because, he’s told, he hasn’t been to college and so can’t be promoted. But instead of taking his case to the EOB, which would seem the logical thing to do, he enrolls in the local community college where, at the suggestion of a friendly dean, he signs up for one course in economics and a second in public speaking. The latter is taught by Mercedes Tainot (Julia Roberts), a woman depressed with her career but especially by her marriage to a layabout lout (Bryan Cranston).

Needless to say, college changes Larry’s life—though he’s already begun the process on his own by trading in his gas-guzzling SUV for a motor scooter. He becomes the star of Tainot’s class, which proves to be a mellowed-up version of “Welcome Back Kotter,” with a bunch of cute, cuddly students that include dumb-but-darling Steve Dibiasi (Rami Malek), who’s obviously intended to be the scene-stealer among them. And when Crowne rescues Tainot, who’s jumped from her hubby’s car after a tiff, from having to walk home by offering her a seat on his scooter, romantic sparks begin to fly.

The Eco class has its effect too—not only in the instruction of the prim, pompous Dr. Matsutani (George Takei), but the presence of Talia (Gugu Mbatha-Raw), one of those fairy-tale sprites that exist only in bad movies. She takes a liking to Larry and not only endows him with a striking new name (“Lance Corona”) but invites him to join the “nice” biker club headed by her boyfriend Gordo (Wilmer Valderrama). She also rearranges his furniture in feng shui style, gives him a new hairstyle, and remakes his uncool wardrobe.

The movie wants to say a little something about workers hit by the current recession, but in that respect it’s a bust—sure, Larry turns his house back to the bank, gets rid of his SUV and moves into an apartment, but he doesn’t appear to have any problem with tuition, and quickly finds a job as a short-order cook in a diner owned by his friend Frank (Ian Gomez). The transformation scenario involving Talia is pure hokum, and the Larry-Mercedes romance comes off as one of those manipulative “Affair to Remember” concoctions that hits every false note.

The frail material defeats virtually the whole cast. Hanks mugs through the proceedings, alternating between near “Forrest Gump”-like obtuseness and sudden flashes of brilliance, while Roberts melts from the frosty wife of the first reel to the lovesick free-spirit of the last ones (goofy laugh and all) as if by rote. Mbatha-Raw is energetic, but her effervescent character is nothing but an artificial contrivance, and the supposedly delightful bunch of Larry’s fellow students in Tainot’s class are all nothing but caricatures, and played as such. Cranston is far too broad—his big screen performances thus far suggest that he’s really better suited to television, where his style works better. And if you’re going to cast Cedric the Entertainer as Crowne’s next-door neighbor, it would be nice to supply him with at least a few opportunities to show off his comic skill. In fact, the one actor who gets some genuine laughs is Takei. Any teacher will appreciate his hostility toward cell phones—one of the few running gags in the picture that works.

Technically “Larry Crowne” is utterly ordinary, with fairly drab cinematography by Andrew Birdzell. In the end it proves a feeble feel-good fable that you’re likely to leave with a very different feeling than the intended one.