My advice? Skip 1 and go straight to 2. Google the story for the first one (Assassin's Creed). The movement and battles are so much more refined in the second.
I only made it an hour or 2 into the 2nd AC before quitting... I honestly thought it was really boring. The story didn't interest me really at all. Dunno, maybe I'll give it a try again sometime, because at the time I was busy with schoolwork as well so I didn't really actually give it too much of a "try" I suppose.