Metal Gear Solid makes me happy in the pants.

I can't decide if the original or MGS3 was my favourite.

Metal Gear Solid had the best story and characters. Nothing beats FOXHOUND. ...well, except Solid Snake. I really liked the jungle setting of MGS3, and had endless fun mindlessly slaughtering animals or alternatively, capturing them and using them against guards. As soon as I find the cobalt blue tarantula, (it's on the walls in the prison area of Granin's lab) every single one of my kills from then on will be through me throwing the little critter onto a guard and having it bite him, slowly poisoning him to death. It's just little things like that which cause me to drool uncontrollably.

MGS2 wasn't a bad game, I just didn't really feel anything towards any of the characters, and no empathy isn't a good thing. Still, I did enjoy the overall plot.