This season, Gotham’s theater companies get risky with a few well-known but seldom-seen revivals.Just take a look at the 2007-08 Broadway schedule: There are textbook classics like “Pygmalion” that might sound to some auds more like required reading than entertainment. The season’s Shakespeare offering, “Cymbeline,” is a complicated, problematic play that few Bardophiles love. And, in its first major Gotham revival, there’s “South Pacific” — a tuner so beloved that a misstep in casting or production could drive away its core aud. In order to outshine the novelty of the competing preems on the boards, producers have to assemble a production that will attract theatergoers who probably already know how the story ends. For Todd Haimes, a.d. of the nonprofit Roundabout, “revivals tend to be artist-driven,” he says. “Pygmalion,” opening Oct. 18, came about when he was talking to David Grindley after the helmer’s Tony-winning “Journey’s End” last season. The production stars two thesps from that revival, Jefferson Mays and Boyd Gaines, as well as Claire Danes. At the Roundabout’s Studio 54, Joe Mantello helms “The Ritz,” Terrence McNally’s 1975 farce set in a gay bathhouse. That show, opening Oct. 11, evolved because Mantello and Haimes wanted to collaborate on something that would fit well in the former disco. “To do a story that takes place at a gay bathhouse in Studio 54, that’s kind of a slam-dunk,” Haimes says. The racy ad image, three hard-bodied men in towels, aims to attract gays while also warning subscribers what they’re in for. “The Ritz,” a farce with a large cast and set, is an expensive proposition. But the resources available to nonprofits — including that cushion of subscribers — help mitigate such risks. So the nonprofit Lincoln Center Theater can afford to explore one of Shakespeare’s obscure “Cymbeline,”opening Dec. 2. The risks associated with LCT’s spring revival of “South Pacific,” on the other hand, stem from theatergoers’ strong affection for the show. For years, the Rodgers & Hammerstein Org held off on a Gotham revival to protect a major jewel in its crown, but one that is also something of a problem child. LCT won over R&H by reassembling helmer Bart Sher with his design team from “The Light in the Piazza,” as well as that show’s actress Kelli O’Hara. Shortly before the 2004 Carnegie Hall concert version of the tuner, R&H prexy Ted Chapin explained why “South Pacific” had never nabbed a Broadway revival. “How do you get an audience back to that post-World War II era in which ‘South Pacific’ was originally staged? There’s something emotionally about ‘South Pacific’ that we’ve been struggling to get right.” In the era of the Iraq War, maybe the time is right.