On 12" Essentials--The Seventies, Polygram at least compiles irrefutable dance classics: Alicia Bridges's "I Love the Nightlife (Disco 'Round)," Peaches & Herb's "Shake Your Groove Thing," Thelma Houston's "Don't Leave Me This Way" and Gloria Gaynor's "Never Can Say Goodbye" --songs that shimmer with a veneer of innocence and genuine good times. God help us if, ten years from now, that's what people will think about Tears for Fears' "Shout" and Soft Cell's "Tainted Love/Where Did Our Love Go." And Trio's "Da Da Da" would never have wound up on The Eighties if it weren't for Volkswagen commercials. That disc's highlights--an entrancing "Word Up" from Cameo and "Seven minutes of madness--the Coldcut remix!" of Eric B. and Rakim's "Paid in Full"--aren't enough to cure the hangover, even if you've been clean and sober for years.