C sharp menu problem with bottons

I am creating a GUI menu but i'm getting some problems.

heres my script

 using UnityEngine;
 using System.Collections;
 
 public class Menu : MonoBehaviour {
     
     private Rect windowRect;
     
     public float boxW;
     public float boxH;
     public float boxX;
     public float boxY;
     
     public float bottonW;
     public float bottonH;
     public float bottonX;
     public float bottonY;
     public float offset;
     
     public GUISkin mySkin;
     public Texture map;
     
     public float textureY;
     public float textureX;
     public float textureWidth;
     public float textureHeight;
     
     public bool on;
     public bool onMap;
     
     
     // Use t$$anonymous$$s for initialization
     void Start () {
     boxW =Screen.width - 200f;
     boxH = Screen.height - 250f;
         
     boxX = (Screen.width / 2) - (boxW / 2);
     boxY = (Screen.height / 2) - (boxH / 2);
         
      bottonW = 196 ;
      bottonH = 33.7f;
      bottonX = boxX / 3 ;
      bottonY = 100;
      offset = 83;
         
     textureX = 239;
     textureY = 86;
     textureHeight = 141;
     textureWidth = 92;
     
     }
     
     void OnGUI() {
         GUI.skin = mySkin;
         
         if(on == true){
         
         windowRect = GUI.Window( 0, windowRect, MyWindow, "Menu");
         }
         
     
     }
     
     // Update is called once per frame
     public void Update() {
         windowRect    = new Rect(boxX, boxY, boxW,  boxH );
         
     }
     
     
     private void MyWindow( int id ) {
         Map();
         if(onMap == true){
         mapTexture();
         }
         Character();
         Sound();
         Grap$$anonymous$$c();
         Save();
         Exit();
 
 
     }
     
     private void Map() {
         
             if (GUI.Button(new Rect(bottonX, bottonY + (offset * 0), bottonW, bottonH), "Map"));
         
              Debug.Log("Clicked the button with text");
         
         //else 
         //onMap = false;
         
     }
     
     
     
     private void Character() {
         
             if (GUI.Button(new Rect(bottonX, bottonY + offset * 1, bottonW, bottonH), "Character"));
     }
     
     private void Sound() {
         
             if (GUI.Button(new Rect(bottonX, bottonY + offset * 2, bottonW, bottonH), "Sound"));
     }
     
     private void Grap$$anonymous$$c() {
         
             if (GUI.Button(new Rect(bottonX, bottonY + offset * 3, bottonW, bottonH), "Grap$$anonymous$$cs"));
     }
     
     private void Save() {
         
             if (GUI.Button(new Rect(bottonX, bottonY + offset * 4, bottonW, bottonH), "Save"));
     }
     
     private void Exit() {
         
             if (GUI.Button(new Rect(bottonX, bottonY + offset * 5, bottonW, bottonH), "Exit"));
     }
     
     
     private void mapTexture(){
         
         GUI.DrawTexture(new Rect(textureX, textureY, boxW  - bottonW - textureWidth, boxH - textureHeight), map, ScaleMode.StretchToFill, true, 10.0F);
         
         
             
             
         
     }
 }
         
     
     
         


 

The problem that I am having is that when I turn on my menu and its bool is set to true ; my botton also gets pressed.