|There is no such thing as a totally trustworthy Web Site. Any site can unknowingly become the host for Malware. If the problem is occuring on the account you use to Surf the Web and not other Accounts you may have picked up one form of Malware or another.|
Try creating a new account for yourself then delete the problem account. Don't transfer anything from the old account untill you have thoroughly scanned your system.
System restore can be your enemy in Malware infections. If you get your account fixed then use System Restore, even for a totally different reason, you are likely to reinfect the Repaired account.
Your choice, but I would disable System Restore till you get things straightened out, then create a new Restore Point.
There is nothing to learn from someone who already agrees with you.