How do I deal with my grandmother who backbites, slanders, and curses, and wants to listen to music on the radio, knowing that she cannot walk?

Part of honoring one's mother is to gently prevent her from falling into sins and to strive for her guidance. This includes occupying her time by discussing the lives of the righteous predecessors, listening to what encourages the remembrance of Allah, reciting and listening to the Quran, and attending scholarly lessons that clarify the prohibition of backbiting. It is also preferable to provide beneficial audio tapes for her to listen to instead of music.