Is it possible to save and email an .m4p file purchased in iTunes such
that it is playable on Windows Media Player? If so, how?

Although it is possible to convert the file to a wma digitally, doing
so is against the terms of service the person who purchased the file
agreed to when opening their account. You could try other music
services where you can buy the file so that it can be played in
Windows Media Player. One example is http://www.napster.com

All the best,

tisme-ga

OK, thanx!