Dead Rising.
A million times over, Dead Rising.
That game and it's sequel were great.
Dead Island on the other hand, was "meh" incarnate.
Playable, yes. Enjoyable, for a little while. But it became bland, boring and all sorts of mediocre adjectives as time went by (specifically after the first bit). It had some nasty exploits and silly systems that you had to wrestle with, whereas the only big problem I thought Dead Rising had was the method of saving.
So if you're one of those select few who managed to not enjoy Dead Rising, I really don't think Dead Island will fare any better in your eyes. In fact, I think it'll probably be worse. But that's just me, who has played both and has formed a strong preference towards one over the other.