Get if Registry entry exists if so do this, if not do that

So in my registry I have the entry under "LocalMachine\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\" called "COMODO Internet Security" which is my firewall. Now what i'd like to know is how can i get the registry to check if that entry exists? If it does do this if not then do that. I know how to check if the subkey "Run" exists but not the entry for "COMODO Internet Security", this is the code I was using to get if the subkey exists.

                using (RegistryKey Key = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\Windows\CurrentVersion\Run\"))
                if (Key != null)
                {

                    MessageBox.Show("found");
                }
                else
                {
                    MessageBox.Show("not found");
                }