Thanks for the responses.
Believe it or not, I actually have some of these “protective shields” that someone had given to me. So I think I’ll try to sprinkle holy water on them first, and then cut them up or smash them, and then bury them. If anyone thinks that’s a bad idea, please let me know.
Also, I know someone else who had broken a laptop out of anger, and the person who he was with at the time (who’s kind of a psychic - or at least truly believes she can feel when great evil is around and just “knows” ), said that the evil spirits/demons that were attached to it had entered him or possessed him afterwards. Is that possible after breaking such an item as a cursed item? And if he did get possessed, would there be any easy way of getting rid of the demons possessing him (besides an exorcism)?