How to stop my character from moving when mouse is clicked.

I am trying to build a simple game where a character falls from the sky and the player clicks on it to destroy it. I am just learning how to use unity and all the commands that come with it but I know how to code. Right now I have written a script to allow the character to fall from the sky in a loop and want it to stop when I click on it. Once I learn that I'm sure I can get the rest. Here's my code: #pragma strict

     var pointB : Vector3;
     var freeze = true;
     function Start () 
     {
         var pointA = transform.position;
         
         while (!freeze) 
            {
             yield MoveObject(transform, pointA, pointB, 3.0);
            
            }
     }
      
     function MoveObject (thisTransform : Transform, startPos : Vector3, endPos : Vector3, time : float) 
     {
         var i = 0.0;
         var rate = 1.0/time;
         
         while (i < 1.0)
             {
             i += Time.deltaTime * rate;
             thisTransform.position = Vector3.Lerp(startPos, endPos, i);
             yield;
              }
     }
     
      function Update() {
     if(Input.GetMouseButtonDown(0))
       destroy();
     }
     
     function destroy()
     {
     freeze = false;
     }

The character continuously falls just fine but doesn't stop when I click on it. Am I doing something wrong?