Metro vanished / disabled (Can't get it back)

I've been using Win 8 Pro for a couple of months now, but a few days ago the metro interface stopped appearing, and I've been unable to get it back. I know a lot of people want it disabled, but I've gotten used to it, and in particular the WIN+I shortcuts for the menu.... The keyboard itself is still functional. I ran a check using OSK, and it shows that the system registers the key as...