You probably have a rogue security software, which is a malware (usually spyware or a Trojan horse) that imitates a legitimate antimalware program. DO NOT click on the bubble, or you have a chance of either:
1.Infecting your system further
2.Your identity being discovered
You should try to boot in safe mode by repeatedly tapping your F8 key as you boot, select "Safe mode with networking". You should be able to open the stuff you'll need in safe mode.
From there once you get to a browser install Malwarebytes Anti-Malware, or you could do a scan with Windows Defender if you have Windows 7/Vista. If so in addition to installing Malwarebytes search for Windows Defender from the start menu.
Also, McAfee is generally not a good program. I recommend Avast or Anti-Malwarebytes.
Edit your question so I can see an update after you've done that.
Edit: Other answerer, System Restore should not be used in a case of infection, as there is a risk the malware will be restored to an earlier date as well.
Ahh the security tool viruis ok re boot the comuter in safe mode and system restore back to the day you bought it then download nortan not macfree and profit
Download this first: http://www.freedrweb.com/cureit/?lng=en
Boot in safe mode by pressing F8 before windows boots.
Run a scan with the downloaded program. Wipes of 90% of infections.