Help with registry permissions

[soleilune]

I've been having some problems with my computer. I had several trojans and worms which my regular antivirus protection did not catch. Finally after scanning with EMCO, Spybot S&D, and SpySweeper, I was able to removed these, however I'm wondering if there is some residual, because I cannot delete old registry entries for the useless firewall "protection" I had -- I receive a message saying error writing to the registry, or permission or access denied. When I run regedt32, in the HK Root directory the only permission listed is "Everyone" and "everyone" has full control. Administrato, Users, Power Users, etc have no permissions at all and are not listed. When I first learned of this, I added administrator and gave them full control, then took away the full control from "everyone". When I went back into the registry I still could not edit the entry so I went back to the registry and the changes had been undone and the added entries had disappeared, with full permission give back to "everyone" Can anyone assist me with this? Thanks very much for any suggestions you can send my way!!