Coding Question But I Don’t Code

I’m looking for a tutorial or some help in creating a form that would change an image based on a drop-down selection.

Imagine an image on a page and below that a drop-down form function. The user would select “green”, for instance and a green image would appear. Here is the tough part: the image should not reset from what ever the user currently selected until the selection is changed via the drop-down. It needs to save its current state.

I’m going to create an page where an admin can change the status of something and then iframe load the image into the blog, but not the form part of the page.

Thanks in advance.