The Boy despairs of my gaming preferences. If it doesn't require at least 1Gb RAM and come on six CDs, it isn't worth the time of day.
He thinks Luddite, I say classically minded. Minesweeper and Tetris are horrendously addictive. Further up the ladder of complexity, the original Lemmings can still never be beat, even if it's a lot harder now to play the original DOS game on an XP computer. I mean, anything where the background music can segue effortlessly from electronic beepy 'O Little Town of Bethlehem' into electronic beepy 'The Good, the Bad & the Ugly' can only be art.
More accessible to a modern PC, and written in very much the same spirit, is Flea Circus (thanks to friend David C for introducing me): it's still all about getting your little creatures from A to B avoiding various obstacles and using a limited set of props. It's a bit like plotting a novel. You know where you're starting from and you know where you want to end up. How you actually get there, goodness knows.