Top of list is
Curse of Monkey Island
Oregon Trails

Many on my wishlist have been mentioned but here's to a little more push behind them
Impressions Games
Lords of the Realm
GameTek, Inc.
The Humans
Westwood Studios (Strategic Simulations ?)
Eye of the Beholder
Infocom
Simon the Sorcerer
Interplay
Lost Vikings
Castles
Sierra
Arcanum
Quest for Glory series (especially 4!)
Caesar series and related games (eg pharoh)
Gobliiins series
Codename: ICEMAN
Rise of the Dragon
The Adventures of Willy Beamish
Betrayal at Krondor
The Incredible Machine
The Black Cauldron
Conquests of the Longbow - The Legend of Robin Hood
Freddy Pharkas - Frontier Pharmacist
Gray Design Associates
Hugo's House of Horrors
Microprose/Firaxis
Civilization series
Master of Magic (Microprose only)
Blue Byte Software/Ubisoft
Settlers series
Origin Systems
Wing commander series
EA Games
Alice
Dungeon Keeper series
Populous series
Theme Hospital
Psygnosis
Discworld games
Lemmings
Apogee Software
Commander Keen
Cosmo's Cosmic Adventure
Bio Menace
Epic Games
Jazz Jackrabbit
LucasArts
The Dig
Full Throttle
Monkey Island series
Day of the Tentacle
Grim Fandango
Afterlife
Activision
Vampire: The Masquerade - Bloodlines
Vampire: The Masquerade - Redemption
Pitfall: The Mayan Adventure
Unknown
Adventure (the text based game, not the Atari 2600 game)

RIM Battle Planets

Axis and Allies by Hasbro Interactive, X-Com, Mechwarrior, X-Wing series, older Civilization games, Starcraft.

Baldur's Gate and Neverwinter Nights series - great adventures, good character development
Civilization series - no need to explain
Disciples series - this got recommended to me by some friend and I would totally like to buy
Discworld - totally, huge Terry Pratchett fan
Diablo - one of my all time favourites
Leisure Suite Larry - allways made me laugh
Monkey Island - love graphics like that and as far as I remember it had nice storyline
At this moment I don't remember anything else except for old Atari games, like Road Race, River Raid or Alley Cat :) I guess we're not going back in time that much...

I would like very much to see these in the Catalog:
Westwood: Nox - A very entertaining CRPG.
Burst Studios: Toonstruck - A point&click adventure released in 1996; quite hilarious, and one of my all-time fav' Adventure games.

If Lemmings 2: The Tribes were on here, I'd buy it in a heartbeat.

EOtB I, II and III would be epic to have

I wish for Planescape Torment as well. It is to expensive to get from ebay/amazon sellers.

yes there is - steam has DRM, GOG no DRM

some good games that haven't been listed
some avalon hill games:
1830
flight commander 2
achtung spitfire
over the reich
cave wars
advanced civilization
history of the world
third reich (not sure if this is a good game but it commands a hefty price for a used copy)
a-sharp's king of dragon pass

I would honestly kill a man for System Shock 1 and 2. Get those running on Vista and I would sell my kidney. Seeeriously.

I wish for RISK II... it was always lots of fun

Definitely old point & click adventure games. By that I mean the Sierra and Lucas Arts classics.

very old (8yr+) and great games:
Internacional Rally Championship - SEGA (AAA Game)
Ultra Pinball 3D - Sierra
Creature Crunch - Class6 Interactive
Cyber Gladiators - Sierra
Hunter Hunted - Sierra (AA Game)
Speed Boat Attack - Hoffmann & Associates (H+a Entertainment)
Rising Lands - Microïds
Comanche 3 - NovaLogic (AAA Game)
POD - Ubisoft (AA Game)
IznoGoud - Microids
Waterworld - Interplay (AA Game)
loved all that