Code:

ShellExecute(Application.Handle, 'open', 'desk.cpl', nil, nil, sw_ShowNormal);

Code:

//Эта функция совместима со всеми версиями Windows

function GetSystemDir: TFileName;

var

SysDir: array [0..MAX_PATH-1] of char;

begin

SetString(Result, SysDir, GetSystemDirectory(SysDir, MAX_PATH));

if Result = '' then

   raise Exception.Create(SysErrorMessage(GetLastError));

end;

procedure TForm1.Button1Click(Sender: TObject);

var

x: Tfilename;

begin

x := getsystemdir;

ShellExecute(Form11.Handle, 'open', Pchar('rundll32.exe'),

'shell32.dll,Control_RunDLL Desk.cpl,@0,3', Pchar(X), SW_normal);

end;