I have just purchased a Dell Inspiron 15 5000 and Installed windows 10 as the Operating system.

I saw a message that an up date was needed. Progressed the update which required a restart. 

The machine went into restart mode with a circle of small dots circling and "restarting" advised. 

It has now been 1 1/2 hours and it aapears that the machine is stuck. It will not switch off 

what should I do?