Some extravagant claims have been advanced for Jonathan Demme’s “Rachel Getting Married,” but I can tell you that Anne Hathaway has likely clinched a Best Actress nomination for her stunning work as a young woman who takes a leave from a lengthy stint in rehab to attend — and wreak havoc — at her sister’s wedding. Working from a knowing (and, rumor has it, autobiographical) script by Jenny Lumet — daughter of director Sidney and granddaughter of Lena Horne — Demme has delivered his most satisfying movie since “Philadelphia,” even if this Altman-esque comedy over-indulges in musical performances and multi-cultural fantasies. It also short changes Debra Winger as Anne’s mother, who has her own issues. If Winger had one more scene, she’d probably get a Best Supporting Actress nomination.