I would have to say the Who, even though Pete Townshend forgot how to write songs after 1973, however. Before that, though, the Who made several classic albums: Sell Out, Tommy, Who's Next (one of the all-timers) and Quadrophenia. Roger Daltrey is arguably the best lead singer of all time...except for Bono, of course.
Led Zeppelin have their share of classics too, but I find that I like their individual songs better than the albums. Their greatest hits discs are excellent, though.
------------------
"Are you saying Boo, or are you saying Boo-urns?"
"Actually, I was saying Boo-ono."