I am trying to use the option to email the form upon submit. It automatically trys to open Microsoft Outlook, but our company uses Lotus Notes. Is there a way to override this so that it opens Lotus Notes as the default email client?
InfoPath only works with the corresponding version of Outlook.
Here are your options.
Use code to send mail via SMTP.
Use server side email such as with MOSS and browser based forms or Qdabra's Web Services.