I came back in about an hour and it was at 72% installing changes, well finally at about 3.30pm it booted to the Start screen, I quite like having the different colours on the tiles.
One thing I've noticed now is that when I go to the Desktop I have this message in the bottom corner and I don't know why or what to do
Yep I have that too as I have secure boot turned off as I boot Mint also.
You can only turn on secure boot if you have UEFI in the bios all new computers have that.
You will need to look at the manual for your computer as not all brands are the same.