Have you played telltale's the walking dead series yet? I just finished episode 5 and cried like a bitch at the end, the best storytelling I've seen in a video game, liked it better than the tv show! This game is far more story based than killing zombies though. (its sort of like an interactive movie)
Regarding dead island, I didn't really like it. It was kinda fun, but clunky and buggy I was disappointed with it.
I play a ton of l4d2 (I'm really into the vs multiplayer). Its a super fun game if you have friends to play with online, but the public players are some of the worst I've seen in any mutliplayer game, filled with trolls and griefers