Hi Welcome to the forums.
You need InfoPath and Outlook to send a form via email. However to view a form does not require these. I just sent myself one to hotmail and it renders read-only in the browser fine.
Outlook is the default for mailing a form from InfoPath. However with the Database Accelerator there is a way to email forms from a backend server and get around this limitation as long as users can submit their forms to a central server.