Antonio Aguilar reigned among the most popular Mexican singers and actors of his generation, recording more than 150 traditional mariachi albums and a staggering 167 feature films during the course of a career spanning more than a half century. Dubbed "El Charro de México," Aguilar invariably appeared on-stage and onscreen in the sequined garb of the rodeo rider, complete with sombrero. His popularity at home was matched by an enormous fan base of Latinos living in the U.S., and in 1997 he broke box-office records by selling out New York City's Madison Square Garden across six...