I pick: Exile/Avernum. (The first remakes, not the remake remakes.) Classic CRPGs full of charming writing and a vast underground world, plus there's Blades of Avernum to make more scenarios.
Impossible Creatures: A lovely Mix & Match RTS where you get to design your army and it takes place in a slightly camp 1930s.
Rollercoaster Tycoon: Ultimately the series that made Chris Sawyer a house name, this game is is programmed mostly in Assembly with a little bit of C, so it'll run on basically anything!
Re-Volt: While the rights to it are dead in the water, this is a charming RC style racer that manages to have a graphical style that manages to hold up to the scrutiny of time; plus there's a community that's been keeping the mods rolling.
Serious Sam: Sometimes you just want to shoot a horde of aliens with little to no plot. And Serious Sam does this with very little jank to get in the way, in spite of it's Eurojank (I use the term affectionately) origins being proudly on display.
Simcity 2000: Because sometimes I just want to sit down and play a technically competent, no-frills citybuilder. Lacking the reward/feedback system of 3K or the too complicated for it's own good deeper sim of 4K, Simcity 2000 fits into that toylike charm Maxis had been making themselves famous for.
The Incredible Machine (any): It's purely puzzles. Paper thin story, and just a pristine puzzle board.
Tyrian 2000: Because sometimes you want a Shmup where you can take things slow and pulverize everything with a massive laser. Tyrian lets you adjust how fast or hard the game is. Though even on the slowest setting, there's always that one level.
Ultima IV: Having rid the world largely of the woes and evils of the past, the people of Britannica were now looking for something to build towards. Lord British in his wisdom, chose to elicit the Stranger, who had helped him rid the world of Mondain and the befouled echos of the First Age of Darkness. He chose to promote the Stranger into the Avatar, and asked that he act upon the virtues of the land, to become an icon for the people to work towards. This is a game with no greater evil to fight, no reason to brute force anything, and a unique goal for a CRPG.
