Here are my takes on what games to play:
Crazy Cars 3 - Nice single player ladder with decent advancements
Star Control - There are two styles of play, ship dual and senarios. Once you get good with ship dualing try some of the senarios
Cannon Fodder - Gets a little repeative but great fun
Dungeon Master - One of my all time favorite games. I like to pick it up every 5 years or so. Last time I was finally able to beat it. Great online resources to help you when you get stuck
Black Crypt - like DM but better looking and MUCH harder
Enjoy!
Bill "tekmage" Borsari