It is actually never too late to get rid of Internet Security 2012, Smart Protection 2012, Security Monitor 2012, System Check, though some suggestions are to format drives as the infections are extremely malicious and damage they causes is unlikely to be repaired as much as to restore system performance to the prior to infecting state. Actually, the rogues tries to scare users. They resets security policies applied by infected system, deletes relevant entry from System Registry and set the lowest possible standard. By doing so the rogues assigns to its executable necessary attributes to interrupt other software and even prevent it from launching, nothing to say of that the rogues itself starts whenever they wants.
Do not trust the scan results by the pretended antiviruses and get rid of Internet Security 2012, Smart Protection 2012, Security Monitor 2012, System Check. Do system backup to the date before infection. That will make your system as robust as before the malware, and the malware will be gone.
Use manual removal guides for Internet Security 2012, Smart Protection 2012, Security Monitor 2012, System Check or launch free spyware scan to get rid of these nasty malwares.