If the Earth stopped rotating or reversed its rotation, the immediate effects would include catastrophic earthquakes and tidal waves due to the sudden halt of surface speed, which is around 1000 mph at the equator. A prolonged stop would lead to extreme temperature differences, with the sunlit side becoming very hot and the dark side freezing, resulting in constant, severe storms. The reversal of rotation would also impact ocean currents and atmospheric conditions, potentially altering weather patterns significantly. Discussions around the topic highlight the absurdity of the question, as it challenges the fundamental laws of physics. Overall, the scenario presents a fascinating yet chaotic vision of Earth's potential future.