I know I've seen other people report this glitch, but I'm not sure what it's called. Anyway, just recently I've been getting this glitch where if I press the Windows button to minimize the game so I can do something else, when I come back everything looks something like this.

I'm not sure why it's started to do this, I've never had a problem before with this. I'm sick of having to restart the game everytime I need to do something else for a minute. Anyone know how to fix this?
EDIT: Sorry the pic is so big.