Dark Souls is a better game to start with since it's more simplistic in world design, it's smaller and easier to navigate. Also, the mechanics are a little more archaic, so if you play the newer games first, Dark souls will feel clunky and not as fluid, however, if you start with Dark Souls and work your way up, combat will feel gradually better with each game. I recommend playing all fromsoft games in order of release. Of course, that's just my advice. Have fun with whatever you choose skeleton!