Computer working problem, msg - dont switch off or unplug power updating 17 of 18 is going on?

it was for several hours nearly a full day it went in this modern times several GBS or GIGA BYTES are installed/copied within a few seconds/minutes why a full day it takes i wonder it was not hanged as i saw some dots moving i was not able to turn off or switch of the computer even if i turn off the power and after some time if i turn on again it is like that only so after nearly one day i get the desktop . againafter a couple of days it shows 3 of four is being up dated and went of for several hours can anybody clarify/suggest whether it is anything like repair ?