You may have been using our system templates quite happily for a while and then you think that in one particular campaign you want to delete the image altogether?
A: The image box itself is inherent to the structure of the template and so the answer is to swap the image out for another image, rather than trying to delete the image box.
Hint: When inserting new images it is always good practice to right click over the image box to find the dimensions in order to re-size your image to make a really good fit for the image box.