New/Load(Continue) in menu

Greetings, Over the last month i have peen working on a game. The game will contain a menu, And in this menu There will be new/Load(Continue) GUI.Buttons In the Menu. But the problem is I am not that good At coding so I seek assistance for this.

i was thinking you could implement this; link text

Here is the script for the menu;

 using UnityEngine;
 using System.Collections;
 
 public class SinglePlayerMenu : MonoBehaviour {
 
     void OnGUI () {
         //background box
         GUI.Box(new Rect(60,50,350,430), "Singleplayer (v1.01A)");
         
         
             
         if(GUI.Button(new Rect(140,130,180,70), "Continue")) 
         {
             
             //PROBABLY A .XML SAVE FILE USED, BUT I'M A N00B, SO YEAH...
             
             
             
             //
             //LOAD SAVE
         }
         
         
         //Delete singlePlayer save file
         if(GUI.Button(new Rect(140,240,180,70), "New")) 
         {
             
             //
             // CREATE/DELETE/OVERWRITE SAVE
         }
         
         
         //Quit button
         if(GUI.Button(new Rect(140,350,180,70), "Back")) 
         {
             Application.LoadLevel("MainMenu");
         }
         
     }
     
 }

If anyone can help please reply .