Roshi win the first one easy
The second is Happosai
I say Roshi for both, since he is not only a prev but kind of a pedophile when convincing Bulma to lift her skirt in Dragon Ball.
You forget, Happosai steal bra and panties from high school girls and grabs a 16 year old girl breasts on a daily basic
Why does everyone think Roshi would win in round one? He can't fight the way he used to in his old age and Jiraiya has powers that Roshi and Happosai can only dream of so Jiraiya would easily win the first round.
Can he tank a moon busting kamekameha?