Collision: I don't know how to phrase what I am asking for

I have a very simple desire for my colliders. If a moving collider's velocity moves it toward or into a wall (static collider) it stops. If a moving collider's velocity moves it toward another moving collider moving in the opposite direction, both stop. If a moving collider's velocity moves it into another collider, the moving collider stops and the other collider does NOT move. Basically, I want to use Rigidbodys and colliders to detect collision detection, but never override the velocity of the objects, except to prevent their motion through another colliders. How do I do this?