Resident Evil in terms of fright and action. I find Left 4 Dead to be more fun to play. It has co-op as well. Actually, L4D can be scary, but rarely. I mean whenever you're about to encounter a tank or some idiot awakens the witch, everybody is like,"Oh Shit". Plus, RE can get very frustrating and annoying sometimes, especially RE4 when you have to protect Ashley. That is a text book definition of "ain in the ass."
Depends on what you're looking for. Both have a different feel and style of a zombie game. I personally choose the Resident Evil because I'm more used to them. Left 4 Dead has a good AI and co-op system.
i havent played either but i heard resident evil 5 sucked bad
It wasn't that it was bad, it was that it wasn't nearly as good as people thought it would be. People thought it would be outstanding, like Resident Evil 4, but it was just an average game.
L4D is good for the co-op action, nothing can be more fun than getting 3 other friends and running through on Expert. Because it's always fun blaming everything on the first guy that screws up. But RE is just so deliciously good, perhaps it's the nostalgia factor going for it (being as it was probably one of my first survival horror games) because it definitely isn't the writing. But RE will win out over L4D all the time, nostalgia beats almost everything.
Those two games are completely different and are only the same because they have zombies, and technically Resident Evil is with parasitic people as opposed to zombies, so there it goes.