Smarty,
Try something like this, go to VBE, from the Microsoft Excel Objects
under your Workbook, select the sheet you want to work with, then paste
in this code:

Private Sub Worksheet_Change(ByVal Target As Range)

If Left(Target.Address, 2) = "$A" Then
If Target.Value = "1" Then
Rows("2:4").EntireRow.Hidden = True
ElseIf Target.Value = "2" Then
Rows("8:10").EntireRow.Hidden = True
ElseIf Target.Value = "" Then
Cells.Select
Selection.EntireRow.Hidden = False
End If
End If
End Sub

Let me know if this is what you were looking for.
Andrew Armstrong