There's not an "old school mode" in that the Start screen will always replace the Start menu and there's no way to reverse that without installing third-party s

There's not an "old school mode" in that the Start screen will always replace the Start menu and there's no way to reverse that without installing third-party software for it. You can choose to only run desktop apps (and set the file associations to desktop apps) and the experience will be 95% the same, though.