Since point&click adventures are my favorite genre and the LucasArts adventures are the best of them, I agree with that.

Since the Lucasfilm / LucasArts games up to Indiana Jones and the Fate of Atlantis never were PC exclusives (Amiga version, FM Towns), Grim Fandango has gone multiplat and Day of the Tentacle is following soon, that leaves Monkey Island 3 and The Dig as best PC exclusives.

Age of Empires 2, technically it's not an exclusive since it had a (terrible) PS2 port but I like to forget about that. Still go back to it after all these years and still have a blast with it.

Came here to say this. Well done young sir

World of Warcraft, but that ship seems to have sailed. For non evolving games it is much harder to choose.

But according to my top 50 games of all time it is Age of Mythology followed by Rome Total War.

My favorite is probably Medieval 2: Total War. Tons of troop variety, a massive map, meaningful technology development, the castles vs cities system was cool, a lot of improvements to the pacing of the game over Rome, and a lot of differentiation between factions. And the AI was actually competent enough to put up a good fight. And the mods earn it another point over Rome, with Third Age: Total War being the single greatest LOTR strategy game ever made and one of the best Total Conversions I have ever played. And of course the expansions/DLC were all great too. Shogun 2 and the original Rome Total War are tied for second, Rome for some real pacing issues and worse AI and Shogun for the lack of troop variety and overly similar factions.

Never played Day of the Tentacle, but of all those you've mentioned (Grim Fandango included), I always valued Monkey Island 3 as the best one of the bunch. Maybe it's nostalgia, its art style or the fact that the puzzle solutions weren't as Moon Logic as some of the other LucasArts games.

I'm glad some people also love this game. :)

Simcity 4

Mario Teaches Typing

Probably The Sims 2 for me.

Definitely not the best, but I think Wolfenstein: Enemy Territory is my favourite.