Edit: This is a list of games that a friend recommended. I wanted to see which one is the most popular. I don't really have a favourite kind of game. I am playing and enjoying "Chocobo's Dungeon" and that's an RPG. I also have New Super Mario Bros. and Super Princess Peach for my DS.
I wrote "not too hard" because I have occasionally needed help with bosses :D So you can just ignore that bit and suggest your favourite games.