Let me go ahead and answer the first part, Yes, the Movesets are insanely different, Examples being moves like Heat Wave, Are crazy amazing in that game, you'd rather have Razor Leaf Than Seed Bomb Etc. But at the same time, very few people in this site really play those games, and you can't really compete, so its basically stacking your pokemon with moves, To get through the game, which in reality falls under in-game things.