that arc you speak of only lasts 6 episodes O_O ( the confining one)
if you wacth the anime only don't open the next spiler
first episode is falls of truth naruto loses against evil naruto, second episode motios and bees histroy naruto finsihs off evil naruto, thrid episode naruto vs fox starts to lose his mom appears, fourth episodehis moms histroy naruto finsishs off fox, fifth epsiode minato vs tobi/fox sixth epsiode guy vs kismae and from tehre it enters the war arc i think O_O