Last night, I turned off my desktop, and when I went to turn it on this morning, it went to a black screen with a mouse cursor. I thought it must be a one time thing, I restarted it, and then it went to my desktop. However, on the bottom right it said there was a driver error, Norton Anti-Virus said there was a problem that needed to be fixed, and I checked and it said that my firewall wall and my anti-virus were off. What should I do, is it a virus or something else?