Beginners has great performances, tells its story in a unique way, and stands out in a special-effects-drenched summer movie season. Buoyed by Ewan McGregor and Christopher Plummer, the film is about a son putting his life on hold to help his father through the last, cancer-ridden months of his life. The father had just begun living again at 75, outing himself as gay and returning to a life that he had put on hold for about a half-century. The son is starting a new relationship, too. Actually, he’s beginning several of them: one with a beguiling French actress, one with a dutiful Jack Russell terrier, and one with himself and his newly rearranged memories of his father.