Abriendo Puertas

Gloria Estefan: Abriendo Puertas (Epic) Between the Spanish lyrics and the proud Latino purity of the music, Estefan's new album may be a bit rich for the average gringo's blood. But those who choose to accept the challenge implicit in the title (which translates as ''opening doors'') might find this spirited collection of salsa and other south-of-the-border styles as invigorating as it is esoteric. B