How to close my C# + Windows application safely...

Hi All

In Exit Menu i am writting code like..
-----------------------------------------

private void ExitToolsStripMenuItem_Click(object sender, EventArgs e)
{
Application.Exit();
close_childForm();
}

public void close_childForm()
{
foreach (Form childForm in MdiChildren)
{
childForm.Close();
}
}

so when the user click File->Exit it will safely close the application... but that NoticyIcon is not cleared from task bar..

Requirement
-----------------
1: how to cler that notify Icon from task bar when the user click file->Exit

2nd problem
---------------
But when the user click 'X'(MinimizeBox,MaximaizeBox,Close) Close Button of MDI some instance remain... as well as NoticyIcon is not cleared from task bar..

so how to close my application safely....


susant
Bombay