In Brief : *** Paul McCartney, “Unplugged--the Official Bootleg,” Capitol.

This loose, acoustic set (recorded live for MTV’s “Unplugged” series) nicely complements last year’s comprehensive “Tripping the Live Fantastic” package, which chronicled the Beatle’s nostalgic “Get Back” tour. Even the most casual Beatles collector will want “I Lost My Little Girl,” the only recorded version of what is billed as McCartney’s first composition, written when he was 14.