Best Mario Party for the gamecube?

So I'm looking for a Mario Party game.  Single Player isn't really a big issue, I will be playing this almost exclusively with 4 players.

The players will be in their teens.  They don't speak english so the mic doesn't factor in too much.   

 Suggestions?  

Also: Any other good party games that might have slipped under the radar?  

I have Mario Kart DD, Smash Brothers, Mario Power Tenis, Mario Golf, and WWE DoR2.

Looking around the net, It seems that 6 was very well recieved. 

 Guess it would make sense that most people only have one MP game.  

Mario Party 4 is the better game.

That said, here are some other party games you missed:
Wario Ware, Inc: Mega Party Game$
Super Mario Strikers
F-Zero GX
Mario Superstar Baseball
Donkey Konga
Bomberman Generation
Sonic Riders