I’d have to utterly agree: Halo is the pinnacle of First Person Shooters, hands down. (Not that those exact words were used.) A good portion of my life was spent on that game and the sequels, i.e., Halo 2 and Halo 3. I competed in a number of local LAN competitions for Halo 1, but when Halo 2 was released I was extremely disappointed, finding it coming up short in every comparative way to its predecessor. Halo 3 on the other hand was a fine piece of work. Maybe it doesn’t have the same curse inducing effects on you and your friends as Halo: CE, but it's definitely cause for an occasional post mortem desecration. Forgive my nostalgia for Halo 1: Backpack Reload, Double Melee, portal killing, grenade jumping, oh and let’s not forget blowing weapons to you via grenades on such classics like Damnation, Chill Out, Hang ’Em High, etc.
As for Doom, that was one of the first for me.