How do you deal with characters in the 128-159 range?

This isn't a PHP issue per say, but I guess a question to other PHP developers.

I've just recently converted everything I got to Unicode UTF-8 which introduced me to the "problems" dealing with characters in the 128-159 range.

Typically my users will copy and paste from Microsoft Word into my web forms which introduces characters like the m-dash.

Obviously I don't want my webpage to show a bunch of ?'s and squares so I have to deal with this somehow, but what is the appropriate way?

Should it be converted to html entities, should they be rejected, will accepting them as html entities introduce other problems such as weird characters when printing or problems converting the page to pdf?

Does anyone have any experience with this?