2/3 of the way thru a restart my MacBook screen turns black

When I restart my MacBook, the grey screen appears, the apple comes up with the scroll bar underneath it, then it scrolls 2/3 of the way and the screens changes color (a muted sepiatone) and the screen goes black and a white spinner comes up about 3-4 times a minute and sometimes you see a white cursor in the upper left hand corner. This can go on all day. I have tried on restart...Command Option PR, N, and Shift Key. I have reinstalled the Sierra software, via one of those restarts and used Utilities to check the Macintosh HD and the system and they are all OK. It does the same thing over and over. HELP!

Chris