Can someone explain difference between msconfig and service manager ?

E.g. sysmain aka superfetch is visible only when you open task manager and go to services, without clicking to "open Services". Okay than if you click on open Services you get to service manager. But than in msconfig there is bunch of services, which doesn't show in either of these previously mentioned windows. It is real mess, windows is full of hidden settings.

So can someone explain to me what is difference when you disable services via msconfig and when you disable them using Service Manager ?

Thanks !

EDIT: can someone explain to me, why some services are accessible only via msconfig and can't be otherwise turned off, only by unchecking them and restarting, which is ton of work, if you wanted to do that always when you game.