What is the best practice for editing fields of a form from a list on an html page?

I have an html page. In this html page I have a table with iterated records from a form. I need the ability to click a button on one of the rows, which will then allow the user to edit only a few of the fields from the form. The primary field that will be edited is a dropdown. What is the best way to do this?

It seems there are multiple routes to go:

From the page, create a stateless form that pops-up or iframe with the fields to edit.
Have buttons that use url variables that correspond with the edits.
I'd assume there are other viable options as well.

What is the best approach? What would you recommend? And is there a test application that I could reference?

Thanks!