Custom taxonomy page that lists content
The quickest way I know of is by using Views.
I would create a special "content type" with a special image field, a text field to describe the meaning of the Tag, and a Term Reference field to include the applicable tag later. Then I would enter one image + text for each existing tag and assign it to the tag itself. Later with the help of views I would customize display-views like the one you have mentioned which would take just a few minutes to do.