Yes, one of the greats... funny that my list of 'adventure game greats' is like 3/4ths Lucasarts including most all the top spots... :)
(in no order) Sam & Max, Indiana Jones and the Fate of Atlantis, The Secret of Monkey Island, The Curse of Monkey Island, Grim Fandango... those are probably my top five... and I mean all adventure games, not just Lucasarts.
I said my top five, not a list of all great Lucasarts adventures... :)
I don't have Sam & Max, actually, but I've heard more than enough great things to know that it's certainly in that top five. Oh, I do have Day of the Tentacle, but it never impressed me as much as the other Lucasarts adventures... it's trying to be funny but IMO doesn't work as well as the humor in Monkey Island. And it's a bit annoyingly hard, with completely random puzzles that make no logical sense at all... I got it and Indy Fate at the same time (CD versions free along with Rebel Assualt in our P90 PC we got in early '95...), and Indy Fate (identifying it from Indiana Jones and the Last Crusade, the other (older) pure adventure Indy game) was, IMO, definitely the better of the two. I haven't played it in years, true, but I sure remember it being great... :) I'd have played it more recently but it's been missing for quite some time now... :(
If I was listing LucasArts adventures I had I'd take those five, remove Sam & Max, and add Escape from Monkey Island, Maniac Mansion, and Maniac Mansion: Day of the Tentacle. Haven't played The Dig. I did play the demo of Full Throttle, though.
Lucasarts has a mix of both humor and serious... I'd say thinks like Indiana Jones and Grim Fandango is more serious (it definitely has humor but the serious side is more important), definitely, than the comedy games like Maniac Mansion and Monkey Island.