To avod 'select':

Code:
     If Not IsMissing(c00) Then
        With Windows(c00)
            .DisplayHeadings = Not .DisplayHeadings
            .DisplayWorkbookTabs = Not .DisplayWorkbookTabs
            .DisplayGridlines = Not .DisplayGridlines
        End With
        Application.DisplayFormulaBar = Not Application.DisplayFormulaBar
      End If