Top fighter game for the GC. First game I got, and I still play it.
Gameplay & Other Things - This game offers the "Classic Mode" which is the mode that was played in the original Super Smash Bros. You go from stage to stage battling characters. After you defeat a character you move onto the next stage. Also in classic mode are 2 minigames. These are Break the Targets, which basically involves you trying to break all the targets within a time limit. Each character has its own unique Break the Targets stage. The second minigame involves you trying to hit trophies falling from the sky into the target zone. "Adventure Mode" is the mode where your character travels through Regular Stages(Like the ones in Classic Mode), or Adventure Stages(As I like to call them). In the adventure stages you start at one point in the stage, and must travel towards the other end. At the end instead of battling the Master Hand, you battle Bowser. When you finish these, you can unlock a third gametype which involves you battling every single character in the game. The other single player game types are Event Matches, and minigames like Target Test, Homerun Contest, and others. The single player is great, and worth playing.
In multiplayer there are many gametypes you can pick from in Special Melee, Tournament Mode, or you could just play regular melee. I play regular melee the most, with MLG settings. If you're getting bored with it, try working in some advanced techniques to help beat your friends with. When you play in multiplayer mode you earn coins depending on what happens in the game. The coins can be used to randomly purchase trophies. Trophies have no real value except for bragging rights. If you don't play multiplayer, I don't really see the point in owning this wonderful game.
Sound - The sound is just about as good as it can be for a fighting game. I liked the background music for the stages, especially for the Majora's Mask stage. :D
Graphics - For a 6 or so year old game I think that these are pretty good. Besides, who needs really good graphics for a fighting game? It's not like because it isn't in HD you won't be able to see you enemy to fight him.
All in all this is a fun game just to hang out and play with your friends. Just don't try fitting in two 100 stock games in one night. You won't even know what's happening halfway through.