Taking its cue from the likes of British imports “The Full Monty” and “Brassed Off,” “Billy Elliot” choreographs whimsy, humor and dramatic social commentary into a crowd-pleasing ditty about a coal miner’s son who’s gotta dance. The film is set in a working-class English town crippled by the bitter miners’ strike of 1984 after Margaret Thatcher ordered the closing of “uneconomic collieries,” and I must warn you that “Billy Elliot” tells a story that is both conventional and predictable. The enjoyment comes from the great charm with which the tale is told. When we meet 11-year-old Billy (played with irrepressible charm by Jamie Bell), things are tough at home without a paycheck coming in. As his dad (Gary Lewis of “My Name is Joe”) and older brother (Jamie Draven) head out to man the picket lines, Billy stays home to care for his senile grandmother. His own mother is recently deceased and missed more deeply by Billy than he is willing to admit. He regularly visits her grave, carrying along scissors to trim the grass around her headstone. Things change, though, when Billy is sent off to the local gym to learn the manly arts of boxing. But Billy is inept in the ring, with his attentions wandering more and more to the other class being taught in the gym. This younger son of a striking miner soon finds himself paying his 50 pence for ballet lessons. Standing at the barre, Billy gets a glimmer of what he was born to do. So does tough, bored teacher Mrs. Wilkinson (a dead-on, no-nonsense Julie Walters), who clearly prefers Billy to the less talented girls in her class. Being the only boy in a room full of tutu-wearing little girls doesn’t bother Billy, but it nearly sends dad and pushy older brother (Jamie Draven) into apoplexy. After all, everyone knows only “poofs” are interested in ballet. Even though his father forbids Billy to attend another class, that’s not the end of his dream. After almost a year of preparation and teaching, Mrs. Wilkinson isn’t about to let Billy miss his chance for a scholarship to the Royal Ballet in London. She confronts Billy’s dad, spelling out for the macho-blurred father just how talented his son is. Dad finally decides this odd talent of Billy’s might be worthy of pride. As stated, the plot is utterly predictable, but the talented cast infuses their roles with such charm the movie rises above its well-worn formula. Supported by the wonderfully nuanced performances of Walters, Lewis and the rest of the cast, Bell makes Billy a kid to believe in. Even at the barre, Bell’s dancing is both good enough and rough enough to make us see his potential. First-time director Stephen Daldry, whose stage credits include the Tony Award-winning “An Inspector Calls,” understands that Bell is the driving force of the movie. Whether foolishly punching out another boy who is trying to console him, bonding with his cross-dressing best friend, Michael (Stuart Wells), or feuding with Mrs. Wilkinson, Bell validates each variation with an engaging enthusiasm. He even makes us ignore the fact that the movie’s climactic audition is really nothing more than a rip-off of “Flashdance.” Finally, one last personal observation. OK, perhaps “rant” would be more truthful: I cannot for the life of me comprehend the logic behind the MPAA’s rating of “R” for this movie. Aside from the odd four-letter-word, there is nothing remotely objectionable about “Billy Elliot.” Especially when those same fine arbiters of taste and moral judgment happily gave such tripe as “Coyote Ugly” a rating of PG-13. Truly, even the homosexual subplot — which has been covered on numerous TV shows geared to preteens — is handled with sensitivity. Perhaps the current batch of Valenti’s vigilantes are all closet Margaret Thatcher fans. Who knows?