INSERTING Calender Option into Cells

One way to to this is via the use of application events and the calander control.
Just as an example, if you wanted dates to be
entered into column1 cells then;
1) Place a calander control on your sheet
should be avail via Toolbox control | more controls
2) Right click sheet tab and select view code.
3) Pates this code in.

Private Sub Worksheet_SelectionChange(ByVal Target As Range)
If Target.Column = 1 Then
ActiveSheet.Shapes("Calendar1").Visible = True
With ActiveSheet.Shapes("Calendar1")
.Top = ActiveSheet.Rows(Target.Row).Top
.Left = ActiveSheet.Columns(Target.Offset(0, 1).Column).Left
Calendar1.LinkedCell = Target.Address
End With
Else
ActiveSheet.Shapes("Calendar1").Visible = False
End If
End Sub

Now if you select any cell in column1 the
calander will show, allowing you to select
a date that is place on the active cell.

HTH

Ivan