Before we push ahead to 8.1, ask your machine's maker if they have all the drivers and more ready.
Hopefully you took the advice on your files and have nothing to lose by going back with the ways noted by Microsoft at link to follow.
Since updating to 8.1 my apps don't open in start screen.. I click on the app..the screen goes directly to the desktop and the blank app screen sits in the desktop tool bar. I can't open any of the programs. I have a Gateway ZX6980 .. Can someone please help?