We are huge Pokemon fans. We own every Pokemon game put out.
The DS will play both Gameboy Advanced games and DS games.
We have Pokemon Mystery Dungeon. DS says it's really fun. You are a Pokemon, not a human. You are a human trapped in a Pokemon body, that is.
You live in a house, have a Pokemon friend, and can go on missions to rescue Pokemon.
You get mail with missions, you can save your money, buy supplies, etc.
You can get Pokemon to join your team, etc.
You can use the little stick with the DS to play, or you can just use the little controls with your thumb like the GBA version.
We bought Pokemon Ranger last Tuesday when it came out.
That game is a little different. You don't get to keep the Pokemon you capture.
You must use the stick with the DS to put circles around Pokemon a certain number of times in order to capture them, but you can't keep them and name them like the other Pokemon games.
Both games my sons say are fun. My younger son says he likes both games equal. My older son says he likes Pokemon Mystery Dungeon because he likes to give the Pokemon goofy names.