Moving Objects along a vertices

OnTriggerEnter happend when something triggers your collider. You cant use do/while loop to do animation in there. It represents one frame. Easiest way:

Have a variable that says wheather door should open or close;

 bool isOpening = false;
 bool stateOpen = false;

When user collides, save the state. Door is now oppening!

 void OnCollisionEnter(Collision collision) {
   isOpening = true;
 }

In update function of door you do this:

 void Update() {
   if(isOpening && !stateOpen) {
     //insert your movement vector * Time.deltaTime.
   }
 }