Block Island, Rhode Island Live life in the slow lane at this isolated escape off the coast of New England.   Ocean Grove/Asbury Park, N.J. A honky-tonk Jersey Shore gem gets rediscovered by bargain-hunting Fire Island exiles.     Cape May, New Jersey A Victorian-era time capsule down the Shore.     Great Barrington, Mass. A bucolic Berkshires town where the arts-and-leisure crowd converges.     Salisbury, Connecticut An eighteenth-century village nestled in the rolling hills of Litchfield County.     Milford, Pennsylvania A wooded, writerly retreat just beyond the Delaware Water Gap.     Mount Desert Island, Maine Lobster pounds and lakeside cottages where the Rockefellers once roamed.   Margaretville, New York A back-country playground for grown-ups in the Catskills. 52 Weekends   Only have a few days to spare? Here are some quick trip ideas.