If my multimeter reads 120v while touching screw with red and ground with black, regardless of whether the breaker is on or off, that means that the breaker is no longer stopping current when off and thus is broken, right?

Most receptacles and switches I have seen are compatible with copper clad wires and as far as I know I can connect CCA wire to them without a issue. However, I'm not sure about splices. NEC 110.14 states [QUOTE]Conductors of dissimilar metals shall not be intermixed in a terminal or splicing connector where physical contact occurs between dissimilar conductors (such as copper and aluminum, copper and copper-clad aluminum, or aluminum and copper-clad aluminum), unless the device is identified for the purpose and conditions of use.[/QUOTE] I cannot seem to be able to find information on whether regular wire nuts are approved for copper to copper-clad aluminum. They only specify wire size, not type of wire. Do I need to use special connector for splicing these with copper?