The big '80s, followed by '90s and '70s, with a bit of the late '60s. I'm 38, a teenager of the '80s who misses his MTV. But two baby boomer older siblings, I got hooked on classic rock (Pink Floyd, Led Zeppelin, Rolling Stones, The Who, The Beatles, Eric Clapton, Steve Winwood, Bad Company, etc) early. My tastes range from the blues (Buddy Guy, Stevie Ray Vaughan, BB King, Albert King, Muddy Waters) to classic rock to alternative to new wave to techno to ambient/electronica to R&B and soul (Marvin Gaye, Curtis Mayfield, etc), jazz, classical, and a tiny bit of country (Johnny Cash, Lyle Lovett, Willie Nelson) and hip-hop (NWA)or trip-hop (Massive Attack).
For the '80s, U2, Peter Gabriel, Phil Collins, The Cure, The Alarm, Depeche Mode, Bauhaus, Guns N Roses, Def Leppard, The Cult.
From the '90s, which was dominated by my college and grad school years, I never got into Nirvana, but liked and still like Pearl Jam, Soundgarden, The Foo Fighters, Tori Amos, Moby, Dave Matthews Band, and dance/electronica from Paul Oakenfold, William Orbit, BT, etc.
As far as the current decade, I've liked the work of Audioslave, U2, Coldplay, Velvet Revolver, Radiohead, Moby, Red Hot Chilli Peppers, Franz Ferdinand, The Killers...
For an all time favorite album--probably U2's 'Achtung, Baby'.