activate menu using the letter 'A'

okay basically i want to activate the graphics option using the button 'A' here is the code:

var BackBoxY : float = 250;

var BackBoxZ : float = 100;

var menu : boolean = false;

function Start()

{

 menu = false;
 

}

function Update()

{

 if(Input.GetKey(KeyCode.A))
 menu = true;

}

function OnGUI () {

 // Make a background box
 
 GUI.Box (Rect (10,10,BackBoxZ,BackBoxY), "Graphics Resolution");

 // Make the first button. If it is pressed, Application.Loadlevel (1) will be executed
 
 if (GUI.Button (Rect (20,40,80,20), "Fastest")) {
    QualitySettings.currentLevel = QualityLevel.Fastest;
 }

 // Make the second button.
 if (GUI.Button (Rect (20,70,80,20), "Fast")) {
    QualitySettings.currentLevel = QualityLevel.Fast;
 }

 // Make the second button.
 if (GUI.Button (Rect (20,100,80,20), "Simple")) {
    QualitySettings.currentLevel = QualityLevel.Simple;
 }

 // Make the second button.
 if (GUI.Button (Rect (20,130,80,20), "Good")) {
    QualitySettings.currentLevel = QualityLevel.Good;
 }

 // Make the second button.
 if (GUI.Button (Rect (20,160,80,20), "Beautiful")) {
    QualitySettings.currentLevel = QualityLevel.Beautiful;
 }

 // Make the second button.
 if (GUI.Button (Rect (20,190,80,20), "Fantastic")) {
    QualitySettings.currentLevel = QualityLevel.Fantastic;
 }

}