Dead Island is a dead game. Most of my FL played it for like a week and now no one is playing. GOW is a bad series. Marble Blast Ultra FTW!
It's comparing apples to oranges. One is a FPS-RPG hybrid with zombies and the other is a TPS full of large burly men yelling swears at the top of their lungs like drunken sailors. So neither is better, it depends on your taste.