Well I figured it out and it was quite an easy fix, I hope it is for you.
I have an MSI motherboard - I pressed DEL to enter setup then accesed the advanced settings menu.
Don't ask me why but the motherboard had decided to change the boot sequence to a usb - I reset it to boot from the hard drive by changing the order.
The first time it took about 10mins - now I can do it in 20seconds
I also learned that instead of powering off the computer using the on/off button, you can hit alt/ctr/del which restarts it.
Best of luck to you!