It might be something called a Hosts file redirect. Do a search for a file named hosts (no extension). Depending on your OS it will be in a path similar to C:\Windows\System32\drivers\etc. If you double click the hosts file, it will as you which program to open it with. Choose Notepad. If you see any reference to this safetyonline.com site or your original homepage in the document, let us know cause that's your problem.
Okay - I did that and did not see any reference to that webpage. Any other ideas?