system
6
Depending on the value of the dword the Internet Explorer-ZoneMap-Domains represents domains in the Intranet Zone, Trusted Sites Zone, Internet Zone, or Restricted Sites Zone. I’m guessing the list your seeing is the Restricted Sites Zone (dword = 4) and you wouldn’t necessarily want to delete addresses listed there. The easiest way to check this is to just look in Internet Explorer under the Security tab.
But what do you mean by dialers?