There is no single behavior that you can make use of in the WA tools that would do this for you. It would require you to use client side scripting to submit the form onchange of the menu. Then use the posted values to trigger the server behavior that will insert or update the record, then redirect back to the page.
It is really the functionality of an insert or update server behavior that you need, you would just like to trigger it based on a client side event rather than the typical form submission. Other than submitting the form with the client side js it is the same as a standard insert or update server behavior.