Yes. You can, but only on monkey smash, which is a fighting challenge. You cannot play multiplayers on adventure mode.
I haven't played for awhile so I am not entirely sure... When you get to the main menu you select the crown that is labeled kong battle, two selections will appear; a battle arena, and a normal kong...
you just eat a banana
no you can't you can buy jungle clim
Just go to Google and type in "donkey kong 64 cheats for n64" and then click on the first link, then youll have them. Have fun playing the game, mate.