2257 confusion and hosts outside of the states

[Tinkerbell]

1.) I didn't realize that as a Canadian I would still be subject to 2257 if I host my site in the states, although I admit it makes sense. Would I still be subject to 2257 if I found a server in Canada or elsewhere (given the site would be available in the states)? And does anybody know of any such hosts?

2.) What exactly is considered obscene? I mean, is there a definition somewhere that is clear so I know what not to put on my site? So far I've avoided showing any genitals.. but do breasts count? And what about pictures where there's obvious sexual activity, but again, no genitals? And what if the picture is merely cropped so that nothing explicit is shown (so that it only shows the model's face, etc...)

I realize this has probably been discussed ad infinitum.. but I searched for 2257 and it came up with a million posts... and filtering through all of them seemed a bit daunting... for such specific questions.

I appreciate the help!