when i woke up this morning, i tried to log into my computer upstairs...much to my surprise, i had no desktop...i've tried rebooting three times and still nothing. i don't know what to do. i have no start button, only a blank screen...that computer has mcfee (spelling) virus protection, as well as something else for spyware...last night when before i went to bed, the only thing up was my email account...no browser or anything else. someone please help...i am very computer simple