Just name the fight that you want to see desperately or that you think is the best fight/matchup.

For me..i wanna see so many fights..such as..
kakashi vs gai
kakashi vs kabuto
naruto vs sasuke (round 2)
jiraiya vs orochimaru
hiashi vs itachi
shino vs shikamaru ..etc..etc..

Though i would like to see all those fights (and more), i'd hafta say the fight i wanna see the most is jiraiya vs itachi.