Which Game (PS3)

[Morthoseth]

Howdy;

First things first, i have a PS3 at home but only ever use it for watching Blu-Rays, though i do have a few games lying around.

I have the following with me at the moment

Killzone 2
Demon's Souls
Motorstorm: Pacific Rift
Uncharted 2
Naruto: Ultimate Ninja Storm
Little Big Planet

I really like the look of Uncharted, however i'd like to know if its worth playing the first one in terms of story before playing through the second?

As for Demon's Souls, that is one game i have played before and ended up putting it down due to the sheer brutality of it, but i'm willing to give it another go ;P

So - what would you do?