* CITY SLICKERS II (PG-13, Columbia TriStar Home Video). Hidden treasure brings a trio of New Yorkers led by Mitch Robbins (Billy Crystal) back to the Wild West in this sequel subtitled ``The Legend of Curly's Gold.'' Although not as clever as its predecessor, which featured Crystal and his crew leaving their comfortable homes to ride in a cattle drive, the film offers plenty of laughs. Jack Palance is back, too, but this time as Duke, the twin brother of Curly the trail boss who didn't live past the first movie. Curly's cowboy hat now belongs to Mitch, who discovers a secret map in it and teams up with his brother, a friend, and eventually Duke to hunt for the missing riches.