Jiraiya sees through the plan of Sasame to poison the group in order to redeem her clan's dignity, as well as to see her most beloved cousin. Moments like these where characters use their head to see through traps are always enjoyable, but this one came with quite a few holes.
The infiltration part of Orochimaru's mansion mansion was pretty lackluster; ironically that Jiraiya avoids being poisoned, but in the mansion falls into a trap rather easily thanks to his taste for women. All the parts were boring, except for the times when Sakura and Naruto continually fell for traps one after another. That part was amusing to see.