An "ActiveX Compatibility" registry key is a result of the "Immunize" function included in some anti-spyware programs (e.g.: "Spybot search & destroy", "Spyware blaster",...)
The key contains the same registry entries as the actual threats, thus preventing them from working correctly. Some anti-spyware programs use this method to prevent launching of the malware. Unfortunately, these parts are still detected by AVG signatures and that is why AVG marks them as infected.
To assure protection provided by AVG against these threats, it is not possible to remove such signatures from AVG virus bases. Because of this, "Immunize" function included in above mentioned softwares is NOT compatible with AVG products.
I have used AVG for years with no major issues but now it looks as though it is going down the over bloated route. There are features in AVG 8.0 which I have not asked for,it has slowed down my boot-up time,and now AVG seem to be adopting the rather high handed attitude that if there are conflicts with other security programs - then get rid of the other progams - you only need AVG. A simple effective AV program is what I am looking for and I think it is time to be looking at the alternatives.