Hello, Human Resources?! - Gamecube ESRB standards in 2005: SEGA vs Nintendo

Star Fox Assault released a month before the E10+ age rating was established.

There are nine endings- ranging from good to evil- and all of them are irrelevant because it all ends up with shadow turning into super shadow and beating up black doom, the games villain.

As for the second question: amnesia, followed by alien invasion. He doesn't have a defined side to take, which is what the player decides throughout the game.