Sounds like you're the victim of some sort of malware. Can you try System Restore to before all this started happening? If not in regular mode, try it in Safe Mode.
I've shortened the subject header because the body of the post mostly just repeated it, and moved the question out of the Help section to Security Awareness/Malware Discussion/Home User Assistance.
This is not a common infection but, interestingly, there were a few reports about it almost exactly one year ago. So perhaps it's one of those that's programmed only to become active on a certain day each year.
Those reports were questions, like yours, that were never answered because no-one knew anything about this (whatever it is). And as the number of reports was very small, it's not a worm or a virus. It may be a Trojan.
The best advice I can offer is to run some of the general-purpose anti-malware tools recommended by Ex_Brit in this document.