Distance and Best Distance

Hi ! I'm new to unity. First sorry for my bad english.

I want to make a distance and a best distance travelled system . I want the distance to be displayed in the game scene and the best distance in main menu scene ... Here is what i have so far.

 //Score
 static var score : int = 0;
 static var distanceScore : int = 0; 
 var distanceFont : Font;
 var style : GUIStyle;
 
 // Checking distance
 var previousPosition : Vector3; 
 var calculatedDistance : float;
 
 
     function OnStart()
         {
 
         }
 
     function Awake()
         {
             previousPosition = transform.position;
         }
 
     function FixedUpdate () {
     
         }
 
     function Update()
         {
             calculatedDistance += (transform.position - previousPosition).magnitude;
             previousPosition = transform.position;
             distanceScore = Mathf.Round(calculatedDistance/0.1);   
             score = distanceScore;
         }
 
 function OnGUI()
 {
 GUI.Label(Rect(0, 50, 200, 30), "Distance: "+score, style);
 }