Kimimaro or Sasuke? (pre time skip with 3 tomoe sharingan) Take note that both can use CS2
Kimmimaro. If he hadnt died, he'd have pwned Gaara.
Shippuden Gaara (with shukaku) or Shippuden Sasuke?
Toughie, but Sasuke, hes probably as strong, if not stronger, than orochimaru now
Shippuden Naruto or Shippuden Gaara?
Naruto but he'd have to open up about 3-4 tails, UNLESS he has the Fuuton: Rasengen
Shippuden Naruto or Jiraiya?
Two words. Sexy Jutsu.
But if they got in a real, serious fight, Jiraiya, hed use that special seal he gives to kakashi to drain naruto's kyuubi power, then pwn him.