Obtener version del Service Pack de Windows

[fide_uci]

Algo como esto se podria uttilizar pero tengo temor de que en versiones de Windows XP u otras que no este instalada la WMI me falle la aplicacion.

procedure  GetWin32_OperatingSystemInfo;
const
  wbemFlagForwardOnly = $00000020;
var
  FSWbemLocator : OLEVariant;
  FWMIService   : OLEVariant;
  FWbemObjectSet: OLEVariant;
  FWbemObject   : OLEVariant;
  oEnum         : IEnumvariant;
  iValue        : LongWord;
begin;
  //Todas las propiedades y metodos de Win32_OperatingSystem aqui:
  //Win32_OperatingSystem http://msdn.microsoft.com/en-us/library/windows/desktop/aa394239%28v=vs.85%29.aspx

  FSWbemLocator := CreateOleObject('WbemScripting.SWbemLocator');
  FWMIService   := FSWbemLocator.ConnectServer('localhost', 'root\CIMV2', '', '');
  FWbemObjectSet:= FWMIService.ExecQuery('SELECT * FROM Win32_OperatingSystem','WQL',wbemFlagForwardOnly);
  oEnum         := IUnknown(FWbemObjectSet._NewEnum) as IEnumVariant;
  while oEnum.Next(1, FWbemObject, iValue) = 0 do
  begin
    Writeln(Format('Caption = %s', [FWbemObject.CSDVersion]));// String
    Writeln('');
    FWbemObject:=Unassigned;
  end;
end;