Yay computer problems. OK my desktop won't display anything on the screen. The computer seems to boot up to the desktop, cause I've heard the jingle when you first get to it. The screen is just black. What could possibly be the problem?
If it's not a graphics issue like previously suggested, then Windows Explorer may be crashing/failing to load upon startup, leaving you with a black screen.
On the slight chance that happens to be the case, hit CTRL+SHIFT+ESC to bring up Task Manager, click on File>New Task>type in explorer.exe. It's more of a band-aid than an actual fix, but it'll allow you to use your PC normally until you find the cause of the issue; likely a registry error.