LEAPING GENRES IN A SINGLE BOUND Likely to be the first Taoist chop-socky extravaganza to cut it as an American art house fave with mainstream crossover potential, Crouching Tiger, Hidden Dragon is nothing if not original. Ang Lee's nineteenth-century tale of two pairs of star-crossed lovers and a psychotic middle-aged villainess (Cheng Pei Pei) begins plainly enough with a worn-out Wuxia knight-errant, Li Mu Bai (Chow Yunfat), visiting his lady love, Yu Shu Lien (Michelle Yeoh), and asking her to safeguard his sword, the Green Destiny. But when the talismanic weapon is stolen--all too obviou...