1. Nine 1/2 Weeks (1986) By day, Elizabeth (Kim Basinger) works in an art gallery. By day, John (Mickey Rourke) makes money by, um, making money. (He's mysterious that way.) By night, they're a seriously fun couple. Director Adrian Lyne's erotic classic features many hot moments--mainly involving Basinger's body backlit by a floodlight. But the sexiest? Try John teasing Liz with an ice cube. Suffice to say, he's not using the thing to fix a drink.
Followed by Ghost and Risky Business. I'm not sure what their criteria are. But for me, I actually quite like the sex scene of Kyle Reese and Sarah Connor in Terminator I. After all, without that moment, there will be no more sequel for Terminator.