MGS1+2 both came out on PC many years ago.
MGS1 was published by MS and is the definitive version of the game.
MGS2 was one of the first PC DVD Rom only games & used an unheard of at the time 5GB to install. Again PC version was definitive but also sluggish should be ok on modern PC's though.
Just searched for Metal Gear Solid on Steam, nothing came up. Do they not realise what an amazing opportunity it would be for the games to be released on Steam? So many great games that are not on there. :/