“Juno” stars Ellen Page as the title character, a whip-smart teen confronting an unplanned pregnancy by her classmate Bleeker (Cera). With the help of her hot best friend Leah (Thirlby), Juno finds her unborn child a “perfect” set of parents: an affluent suburban couple, Mark and Vanessa (Bateman and Garner), longing to adopt. Luckily, Juno…