I can't believe some of these lists. While I love them, I can understand not liking the Grateful Dead, but The Who? The Clash? What do you have against rock 'n' roll?
I'll give you six and break it down by decade:
1950s - Pat Boone (OK, not a band but an artist and everything that was wrong with the white-bread-itization of rock 'n' roll in the 1950s)
1960s - The Osmonds
1970s - Tony Orlando & Dawn
1980s - Air Supply
1990s - 'N Sync
2000s - The Flaming Lips