RAISE TWO VOICES: There's a different sort of music on Dweezil Zappa's new album (F21). His heavy metal remake of the Bee Gees' "Stayin' Alive" originally featured the vocals of Ozzy Osbourne. But when Osbourne's record label stalled in granting permission for Zappa to release it, he turned the vocal spotlight over to the next logical choice. . . . Irvine's own Donny Osmond. Says Zappa, "He gets so much flak for being Donny Osmond, you know?" But "there's no denying he's a great singer."