Very simple example to show what i think you want. Make a form, with a label, and two buttons, IF you click the first button starts the timer ( <timername>.start() ), second button ( <timername.stop> ). The rest you should be able to get from the code below.
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Timer1.Start()
End Sub
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Timer1.Stop()
End Sub
Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
Label1.Text = DateTime.Now()
End Sub
End Class
The attached is a all the files from my little test project, made in VS2005 SP1.