Is hanging a blue palm with Qur’anic verses written on it on the wall for decoration forbidden (haram)? Is it considered an amulet? And if so, how should it be disposed of?

If by "blue hand" you mean a piece of wood inscribed with Quranic verses and hung on the wall for remembrance, then there is no objection to it, provided that it is not for the belief of warding off the evil eye and envy. In that case, it is not permissible.