Folding (Fallout 3)

(for grammar sorry I'm not Russian )Zdrastvuite , I'm playing fallout 3 game of the year edition clean without mods and so dalie on steam, but I have a problem only one I minimize the game and back Ana vozvrashatsa nehochet the sound is all there but shows me my desktop and not ihru I would like to ask maybe someone knows how to ispraviti this, by the way I have windows 8.1 .
Who can help really want the devil to play a Windows mod spoils the atmosphere of the game .