Phone bill cramming and long distance issues

This hasn't happened to me yet, but I have heard of other people having issues with third party scams where they "cram" a phone bill with fraudulent charges.  Is there a way to get Cox to forbid all third parties from being able to bill anything to our phone bills?

Also, I use my cell phone for long distance calls (which is free or included as part of my monthly minutes charges).  Is there a way to disable long distance on my landline phone from Cox?