I've always wanted to play Day of the Tentacle. And Grim Fandango.

yeah, DOTT was great, and the riddles and puzzles were entertaining :)
Also loved the Dubbed Version, the German Voices were great :)

Every Star Wars game known to man, of course.

But some high ones on my list:

Outlaws (I loved that game)
TIE Fighter (lost the disc, bought the new addition, lost it again)
XWing Alliance (I have a disc somewhere around here...)
Star Wars Rebellion (don't have the original disc, but I luckily made a backup. But it's so old that I doubt it works anymore)

All the adventure games. TIE Fighter. KotOR 1.

It's pretty much redundant to list which LucasArts games we want here. GOG knows that everybody wants these games, and that any LucasArts game will sell well. The only thing preventing this from happening is LucasArts.

sweet outlaws would be great but they got to bring in the scumm engine games

Curse of Monkey Island Games
Full Throttle
The Dig (one of my all time favorites)

Everybody who didn't say "Tie Fighter Collectors CD" will get force chocked!

... but DOTT would be nice too ... ;-)

I'm one of the few people who loves adventure games, but does not care for Day of the Tentacle.

Now, believe me, I get it. It's well-designed, great puzzles and all that. But I hate the style, I hate the voice acting compared to other LucasArts games of the time, and most of all I hate that it's a sequel to Maniac Mansion. Because even if it's a great game, it's a horrendous sequel, and I hold Maniac Mansion very dear to my heart. I think it was way ahead of its time, and that it really showed what the adventure genre COULD be. Relatively speaking, its sequel played it pretty safe.

Sell Maniac Mansion separately, please? With a hint poster printout and everything? I don't want to have to own Day of the Tentacle. I don't care for it.

All of them.

Grim Fandango,simply because it has major problems running on modern systems,and needs the update that GOG will have to give it. The other Lucasrats adventure games run great with Dosbox or Scummv, but Fandango does not.
After that, Full throttle or Afterlife.

Of the Star Wars stuff, I agree with the original X Wing /Tie Fighter games (The single player ones,;The 1997 Multi Player oriented X Wing vs Tie Fighter is not bad, but is nowhere near as good as the two originals) and Star Wars Alliance (which was the real sucessor to the original X Wing/Tie Fighter games); and Star Wars:Rebellion (not quite as good as it should be, due to a not that well done interface, a serious flaw in a game this complex,but it;s a 4X strategic Star Wars game, the only real one to date).
Outlaws was a lot of fun.
Dark Forces:Jedi Knight is available on Steam, but the programing for a modern computer was very badly done (No Music, and you have to play it with 2D graphics,they did not bother to update the 3d Graphics in the game) and for that reason it should be on GOG if GOG will do the update right.
I love the Monkey Island games, but to be fair to Steam, they did do a very good job with the updated version now availble.

BTW Maniac Mansion is included in DOTT; any of the many fan websites for Lucas arts adventure games will tell you where it is hidden.
In addition, there is a port to a modern computer called Maniac Mansion Deluxe. I am not sure of the legality, but Lucasarts has not bothered the people who made it so they probably do not care.

Sam and Max. I want to play the Sam and Max games, but well, I'm poor, and I want to play the first one. Of course, I'm terrible at adventure games, so I also really want Outlaws.

Indiana Jones and the Infernal Machine

my fav game but the disc is kaput!

...and Super Mario Bros 3 is a platformer that doesn't get nearly the love it deserves. -_-;

Seriously, in what universe is Grim Fandango underrated? Is it the same universe I keep hearing about where nobody bought or played Psychonauts? :O