Well, first of all, I have to say that I dont speak english quite good, so I apreciatte the effort that you guys are doing trying to understand me. (:
My question was: I supose that if you use a combination of shield and sword, obviously one button will use the shield, blocking the incoming atacks, but if for example, you dont equipe a shield, you use... mmm a magic spell and a mace, what button will be used to block? In that case, there should exists three buttons: one for the right hand, another one for the left hand and a last one for blocking, but if you are using a shield, the button for blocking and the button for the hand that holds the shield have the same effect?
I really hope that you guys can understand my questions, thanks!
Actually with sword+shield I think you still have to tap both mouse buttons or gamepad triggers at the same time if you want to block, because if you just press the button that controls your shield hand, it will try and do some kind of shield bash (I'm not %100 sure though). The same idea goes for dual wielded weapons -- you would have to push both buttons simultaneously to block.
You can't block with a sword in one hand and a spell in the other, because I think your free hand (the one without the weapon) is needed to help you brace the weapon with two hands when you try and block with a one handed weapon.