procedure TForm1.Button1Click(Sender: TObject);
var
Wnd: hWnd;
buff: array [0..127] of char;
Begin
ListBox1.Clear;
Wnd := GetWindow(Handle, gw_HWndFirst);
While Wnd <> 0 do Begin // Не показываем:
If (Wnd <> Application.Handle) // Собственное окно
and IsWindowVisible(Wnd) // Невидимые окна
and (GetWindow(Wnd, gw_Owner) = 0) // Дочерние окна
and (GetWindowText(Wnd, buff, sizeof(buff)) <> 0) Then Begin
GetWindowText(Wnd, buff, sizeof(buff));
ListBox1.Items.Add(StrPas(buff));
End;
Wnd := GetWindow(Wnd, gw_hWndNext);
End;
ListBox1.ItemIndex := 0;
End;