I would have to go with Jiraiya. I'm not a big fan of evil characters, especially of one that looks like Michael Jackson [Orochimaru]. xD
I think that if both were at full power Orochi would come out on top. Here are some reasons why i think this. For one what did both sanin do during the 30 or so years they were gone- as far as we know Jiryia was writing erotic novels and taking peeks at women for "insperation", on the other hand Orochi did all he could to learn and make new powerful jutsu's as well as take over peoples body's to get their kekki genki. During the three summon fight Manda was holding his own agianst the slug and toad, and without tsunade assistance i think he would of won.