Security Center: System Restore For Firewall?

I recently installed Comodo Firewall and once again, it was too much for me to handle, so I uninstalled it and went back to Windows Firewall until I can find something else. However, as most people experience, it is still listed as my running firewall in the security center. I googled the problem and I have tried everything that I have found to get rid of it and it will not go away! I followed the instructions on the Comodo page and when it comes to deleting the repository file, it won't allow me to. I hit delete and it comes up that a file is still in use. I tried again and again, went under safe mode, and nothing. I tried to run the Command line....it tells me the repository file is not empty and Command will not let me proceed any further.

I tried System Restore, which solved the firewall problem but brought on antivirus problems (I have the Avira free edition). The AV guard will not work. I click "Antivir Guard Enable"....nothing. The definitions remain at the day I restored back to and when I try to update, it says my program is up to date. I go to the Service program under Administrative tools to start it, same problem. I have restored back a couple times and have never had this problem. So I ended up undoing both system restores and am back to the firewall problem. I can't get rid of it no matter what I do.