I love the Rock- and I want him toss me around, but he's just not sexy to me. If I had to choose between the two it would be Efron. He's more my age and he's pretty.
But to be perfectly honest I'd rather have Adam Scott in a ratty old Letters to Cleo t-shirt. Mmmmmmmmm.
The Rock because he's fucking amazing. ( but is he amazing at fucking? hmmm... I'll report back if I should ever find myself in this situation for real).
While I still think I'd go with the Rock, I answered before I saw @natariru's picture of Zac. He 's grown up a bit from the initial mental image I had.
I picked the Rock because I just like him better. And also I'm in the Zac would make me feel like a dirty old lady camp. (Although I just googled it and I would have had to be a VERY young teen to be his mother, so that makes me feel a little better).