Halo is the game that brought me into the first person genre (yes I'm of the younger generation) and is well... sweet.
Looking back on my experiences with Halo, I think , "It reall wasn't all that special, was it?" But something about it is just addictive and immersive and makes it worthwhile for me to play the single player over and over and still play the PC version with my friends online and over a LAN. Anybody who has any interest in first person shooters ought to play both Halo's, and if not both and least Combat Evolved. You don't have to be one of the twelve-year old raving fanboys to enjoy it. It's an awesome game anyway.