@stuartk - my favorite years for them would have to be '77-'78. And to tell you the truth, I don't think I've ever heard 'Ladies and Gentlemen' or most of the other official live stuff except for Dicks Picks and all of the annual packages...
My favorite of those packages is '30 Trips Around the Sun', which has one show from every year from 1965 (Pig's and Jerry's voices sounded very different at the beginning before they found their own style, and you can hear 'em do 'Cosmic Cowboy' and other songs never to be heard again!) to 1995, and the shows they picked were real 'on' nights, one and all...
Of all the post-Jerry Grateful Dead bands, the one I like the most is Dark Star Orchestra; they are incredible and at this point they've played WAAAAY more shows than the boys ever did. Phil said that GD music was its own genre; I agree and to me, DSO is the most traditional GD sound, including the vocals; their Lisa is a stunning singer; so much more powerful (and in tune) than Donna ever was.

