Question about silver colored wires from a tv

Cut through them to make sure that you're not just looking at a coating. I've seen some monitors that have used coated copper there.

Your yard may classify things differently, so I'd take a sample to them to be on the safe side.

Tinned copper. If left unstripped, it's #2 or #3 insulated, depending on the insulation/copper ratio and how your yard grades it. If it's bare, it's #2 copper.