Earliest I can remember is playing Need for Speed Hot Pursuit back when I was 8 years old or less. I don't know if I played anything else at that time, as that's all I remember playing until my cousin brought me a game demo disc with Age of Empires 2: The Conquerers on it and I was hooked on strategy games.
I'll ignore the default games that come with a Windows system.
My first PC game was Atomic Bomberman. Rude, crass, but some how really funny. I still have the game, but can't play it, it's too old for my laptop. Too old I tell you! Pity, it also made the BEST screen saver when you stuck a bunch of max-level computers at it with a 99-game match requirement.
--- The best laid plans don't last a second in real life. In the end, all you can do is bum-rush your objective and hope for the best.