Having watched the ‘79 Game Seven game on TV, in southern NH surrounded by Bruins fans (except my dad), I (with all due bias, not going to try to hide it
) concur with your notion that it should rank as the greatest moment in NHL history—especially for the collective look of disbelief and, shortly afterwards, depression on the Bruins fans’ faces. Obviously open to debate re: Habs win, I also agree with your view of the “Orr goal” as highly overrated (but among the best sports photos ever taken, of that there is no doubt).
If I were to pick a non-“homer” moment (in my lifetime, so going back to the first modern expansion in ‘67), I’d have to go with M-A Fleury’s save in the dying moments of the 2009 final to preserve the one-goal lead and win the Cup. (I’m no fan of either the team or the player, but it was a spectacular moment to see).