The 1960s were the best. Basically a no contest, despite there being plenty of good stuff from the other decades.
I'd agree that the best music was produced in the 60s, the problem is that it was quite literally roses being plucked from the middle of the snowbank; for every "Light My Fire" there's a "Ballad of the Green Berets" to go along with it; plus you have to consider the first half of the decade (in which there was pretty much nothing produced that people still listen to) as well as the second.
The first half of the 60s had some great early Dylan, Beach Boys and Beatles stuff as well as some classic doo-wop. There's plenty of stuff I enjoy from that period.