Welcome to bleepingComputer.
I can't say I have come accross a screen as such before, so let's work the problem. Has anything changed? Have you loaded any new software, or added any devices to your system? I am looking for cause and effect.
Next, do you have up to date virus protection? Have you scanned for any spyware/adware/malware?
I would suggest following this post: Start here
It will take you through scanning for viruses, and checking for malware issues. All the software found in the guide is free.
try it and let us hear from you...
"In a world where you can be anything, be yourself." ~ unknown
"Fall in love with someone who deserves your heart. Not someone who plays with it. Will Smith