> What are the names of the actors who played Stacy and the boy who has a crush on her mom?

If you are talking about the video for "Stacy's Mom" by band "Fountains of Wayne". Stacy was Gianna Distenca, the boy was Shane Haboucha and the hot mom was of course model Rachel Hunter.

See:
http://en.wikipedia.org/wiki/Stacy's_Mom
http://en.wikipedia.org/wiki/Shane_Haboucha
http://en.wikipedia.org/wiki/Rachel_Hunter