Como obter informações do s.o. (nome, versão, compilação)?

Unit sobreManager;
interface
uses Windows, SysUtils, Classes, Graphics, Forms, Controls, StdCtrls, Buttons, ExtCtrls;
type
TfrmSobreManager = class(TForm)
btnOK: TButton;
ProductName: TLabel;
Version: TLabel;
Label1: TLabel;
Label2: TLabel;
Label3: TLabel;
Copyright: TLabel;
Panel1: TPanel;
Image2: TImage;
GroupBox1: TGroupBox;
Bevel1: TBevel;
stOSVersao: TStaticText;
stOSBuilder: TStaticText;
stOS: TStaticText;
stOSService: TStaticText;
procedure FormCreate(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;
var
frmSobreManager: TfrmSobreManager;
implementation

{$R *.DFM}
// VERIFICA E APRESENTA AS INFORMAÇÕES do SISTEMA OPERACIONAL
procedure TfrmSobreManager.FormCreate(Sender: TObject);
var
verInfo : TOsVersionInfo;
str : String;
I : Word;
begin
verInfo.dwOSVersionInfoSize := SizeOf(TOSVersionInfo);
if GetVersionEx(verInfo) then begin
stOSVersao.Caption := 'Versão : '+ IntToStr(verInfo.dwMajorVersion) +
IntToStr(verInfo.dwMinorVersion);
OSBuilder.Caption := 'Compilação : '+IntToStr(verInfo.dwBuildNumber);
str := 'Sistema Operacional : ';
case verInfo.dwPlatformId of
VER_PLATFORM_WIN32s : stOS.Caption := str +'Windows 95';
VER_PLATFORM_WIN32_WINDOWS : stOS.Caption := str +'Windows 95 Osr2 / 98';
VER_PLATFORM_WIN32_NT : stOS.Caption := str +'Windows NT';
end;
str := '';
for I := 0 to 127 do
str := str + verInfo.szCSDVersion[I];
stOSService.Caption := 'Informações Adicionais : '+ str;
end
end;
end.