Visual Basic.NET - Saber la resolucion de la pantalla

Dim pantalla As System.Windows.Forms.Screen = System.Windows.Forms.Screen.PrimaryScreen
MsgBox(pantalla.Bounds.Width.ToString() + "x" + pantalla.Bounds.Height.ToString())

Y para ajustar el tamaño de un formulario a la resolucion de la pantalla :

Dim F As New frm_menu_informes
f.StartPosition = FormStartPosition.CenterScreen
f.Size = New System.Drawing.Size(CInt(pantalla.Bounds.Width.ToString() ), CInt(pantalla.Bounds.Height.ToString() ))
F.ShowDialog(Me)
F.Dispose()
F = Nothing