5. Again, right click at an empty area on the right pane, select NEW > DWORD Value and type DisableStatusMessages. By default, the value data should be 0. Leave it as it is.
Now when you restart your computer, it will very quickly show you the DLL files that is executed during Windows is starting up screen. When you shutdown, it will tell you that it is playing logoff sound, stopping windows file protection, windows is shutting down and etc… Let's say if it hangs a long time at Playing logoff sound when you shutdown your computer, you now know for sure that this shutdown problem is caused by the wave file being used for Windows LogOff.
If Windows hangs at "Windows is starting up" and unable to get in Windows or safe mode at all, sorry to tell you that you won't be able to use reg.exe in Recovery Console to modify your registry because it is not supported and will only tel you that the command is not recognized. There is a way to edit the registry offline by using BartPE boot CD. You can check out the guide here. You can also try running scandisk to scan your hard disk for problems, sfc to check system files, and finally windows repair or reinstallation to try to fix the problem.
As you can see, there is no harm or performance loss in enabling Windows verbose status message. In my opinion, Microsoft should have enabled this feature by default! Good luck in fixing Windows startup, logoff, login and shutdown problems!