_Stairway to Heaven/Highway to Hell_ - Mercury, 1989 Another benefit album, for the Make a Difference Foundation. All covers, of artists affected by drug problems. Most of the tracks are strong: "My Generation" (Gorky Park), "Holiday in the Sun" (Skid Row), "I Can't Explain" (The Scorpions), and "Purple Haze" (Ozzy Osbourne) all rock well. Three takes by hair bands-- Motley Crue on "Teaser," Bon Jovi on "The Boys Are Back in Town," and Cinderella on "Move Over"-- aren't bad, either. The last two tracks feature all-star line-ups. They're okay: "Drum Madness" and a medley of "Hound Dog, Long Tall Sally, Blue Suede Shoes, and Rock & Roll."