William Makespeace Thackeray’s beloved novel gets another filmic adaptation, and if the sprawling lushness of its epic length is lost in the reduction to two and a half hours, that’s more than made up for by wickedly witty humor, sumptuous visuals, and the delightfully impish Reese Witherspoon (Legally Blonde 2: Red White and Blonde) as heroine Becky Sharp. Director Mira Nair — no stranger to pointed but affectionate social satire; she made the delicious Monsoon Wedding — revels in Thackeray’s lampooning of genteel class warfare, spreading upper-