A Macro Error

Hi,

First of all, I have no knowledge of macros or VBAs, I only try to find some useful macros on the net to use when necessary. I have found two such macros recenly, and they work well separately, but not on the same macro page. I keep getting "Compile Error: Ambiguous name detected: Worksheet_Change" I tried to figure it out on my own and it seems to be about two macros having the same name or something.
Private Sub Worksheet_Change(ByVal Target As Range)

If Range("'D13") = "New" Then
        Rows("7").EntireRow.Hidden = True
    Else
        Rows("7").EntireRow.Hidden = False
    End If

End Sub
Private Sub Worksheet_Change(ByVal Target As Range)
    Dim oneCell As Range
    On Error GoTo ErrorOut
    For Each oneCell In ActiveSheet.Cells.SpecialCells(xlCellTypeAllValidation)
        If Not oneCell.Validation.Value Then oneCell.ClearContents
    Next oneCell
ErrorOut:
Application.EnableEvents = True
On Error GoTo 0
End Sub

So, I tried to delete the second name, it stopped giving the error, but the first macro with if function stopped working.

Private Sub Worksheet_Change(ByVal Target As Range)

    If Range("'D13") = "New" Then
        Rows("7").EntireRow.Hidden = True
    Else
        Rows("7").EntireRow.Hidden = False
    End If

    Dim oneCell As Range
    On Error GoTo ErrorOut
    For Each oneCell In ActiveSheet.Cells.SpecialCells(xlCellTypeAllValidation)
        If Not oneCell.Validation.Value Then oneCell.ClearContents
    Next oneCell
ErrorOut:
Application.EnableEvents = True
On Error GoTo 0
End Sub

I want them both to work at the same time, could anybody help? Thanks in advanced.