First complete arcade mode. When selecting Jinpachi pressing SQUARE yields his Dark Resurrection fiery demon form. TRIANGLE grants you his human form. And CIRCLE and X will get you his original Tekken 5 demon form.
Beat the arcade mode three times and the entire stage list from Tekken 5 will be unlocked for use in versus play.
Select the bear by pressing Circle at the selection screen.
Chgoose Yoshimitsu at the selection screen with X or Circle for normal form, Square for dark ninja form, or Triangle for purple skinned ninja form.