I have a 6 month old computer that my nephew built for me because I do not know much about computers. When my wife turned the computer on Monday it gave her a message about the computer not having been shut down properly. When she attempted to restart using an earlier version of the computer setup she got a blue/gray AVAST screen that has a safe-mode icon in the upper left, and avast icon in the lower left and a green "switch" button in the lower right. When I click on the switch button it shows me my desktop for a split second, but does not switch. When I click on the avast button it does NOT let me shut it down. When I click on the safe-mode button it does nothing. When I hit CTRL-ALT-DEL I can go into file manager, but cannot manually shut down. I am not tech savvy and cannot figure out how to even make my computer work at this point. It is Windows 7 64 bit. I am not sure what else to describe at this point.