Can word 2007 be set to only have 250 words per page?
No, not really.
You can turn on the word count in the status bar at the bottom of the Word
window (right-click the status bar and click Word Count). As you approach the
end of each page, select the page's content and look at the word count. It will
show something like
Words: 245/734
which means the selected text contains 245 words out of a total of 734 in the
document.
If you want to standardize the number of lines per page (and assume an average
number of words per line), see
http://sbarnhill.mvps.org/WordFAQs/BottomLine.htm.