...
proceduere TForm1.FormCreate(Sender : Tobject);
var
 WinVer : TOSVersionInfo;
 I      : integer;
 tmpStr : sring;

begin
 with WinVer do
  begin
    dwOSVersionInfoSize := SizeOf(TOSVersionInfo);
    if GetVersionEx(WinVer) then
     begin
       Memo1.liens.add(IntToStr(dwOSVersionInfoSize));
       Memo1.liens.Add(IntToStr(dwMajorVersion));
       Memo1.liens.Add(IntToStr(dwMinorVersion));
       Memo1.lines.Add(IntToStr(dwBuildNumber));
       
      case dwPlatformId of
       VER_PLATFORM_WIN32s: 
          tmpStr:='Windows 3.xx in with 32 bit';
       VER_PLATFORM_WIN32_WINDOWS:
          tmpStr :='Windows 95 or above.';
       VER_PLATFORM_WIN32_NT:
          tmpStr := 'Windows NT';
      end;

      Memo1.lines.add(tmpStr);
      tmpStr:='';
      for I:=0 to 127 do
        tmpstr:=tmpstr + szCSDVersion[I];

      Memo1.lines.add(tmpStr);

    end; //If 
 end; // Case
end; //Procedure
.....