That is what VATS is for. Unless they change the combat system that's existed since the first game, you have the option of either real-time shootin'/stabbin'/punchin'/grenadin', or entering VATS mode, where your dexterity score gives you action points to attack with and your perception score and skill with your current weapon gives you a specific percentage chance of hitting one or more body parts. It gives you a moment to stop and think, and it puts the aiming burden on the character and the weapon rather than on the player.