What video game should I get?

[PokerBob]

I am not much of a video game guy. 8 years ago when the new Frogger game came out for Playstation, a friend of mine stayed up all night and called in sick the next day so we could solve the game. I don't think I've played a game since. I am intrigued by the new Godfather game, and I have been told that Civilation 4 is a cool game. I'd rather not buy an Xbox or whatever and would prefer to just play it on my computer, which only really gets used for poker and porn. Thoughts?