This type of configuration can be performed by an admin that is hosting the application locally.  In the event that you are outsourcing the application hosting, then you will have to put in a request for these changes.

If you can make the edits to the web.config located in the root directory of your application then take the following steps for modification to suite your needs. 

Note that all other text is not configurable and is hardcoded into the application.

Password Reset Mail

Password Change Confirmation