private void Form1_Load(object sender, EventArgs e)
  {
      IdleTimer.Tick += new EventHandler(IdleTimer_Tick);
  }

  void Application_Idle(object sender, EventArgs e)
  {
      if (!IdleTimer.Enabled)
      {
          StartTimer();
      }
  }

  private void StartTimer()
  {
      IdleTimer.Interval = (Int32)((60000.0D) * (0.2D));
      IdleTimer.Enabled = true;
      Debug.WriteLine("Timer Started : " + IdleTimer.Interval.ToString());
      IdleTimer.Start();
  }

  void IdleTimer_Tick(object sender, EventArgs e)
  {
      IdleTimer.Enabled = false;
      // Some cleanup code
      // ....
      // ....
      Application.Exit(); // Or something like this
  }

  private void Form1_MouseMove(object sender, MouseEventArgs e)
  {
      RestartTimer();
  }

  private void Form1_KeyDown(object sender, KeyEventArgs e)
  {
      RestartTimer();
  }

  private void StopTimer()
  {
      Debug.WriteLine("Stopping Timer.");
      IdleTimer.Enabled = false;
      IdleTimer.Stop();
  }

  private void RestartTimer()
  {
      StopTimer();
      StartTimer();
  }

private void Dashboard_Load(object sender, EventArgs e)
    {

        Application.Idle += new EventHandler(Application_Idle);
        this.KeyPreview = true;
    }

public static uint GetIdleTime()
{
     LASTINPUTINFO LastUserAction = new LASTINPUTINFO();
     LastUserAction.cbSize =
(uint)System.Runtime.InteropServices.Marshal.SizeOf(LastUserAction);
     GetLastInputInfo(ref LastUserAction);
     return ((uint)Environment.TickCount - LastUserAction.dwTime);
}

timer1.Start();

private void timer1_Tick(object sender, EventArgs e)
{
    if (GetIdleTime() > 1200000 )  // 20minutes
       Application.Exit();//For Example
}