There's no such thing as web page for filtering content. As long
as it fits the criteria that the admin sets, you will see it.
For DansGuardian, there's no way you can remove it because it's not
installed on a PC. Rather, it's installed on a server. All packets
will route through this server and be inspected. If it pass, you
will see the website. If it fails, the website that you wish to go
to will become DansGuardian warning message.