Re: how to not show images?

[None]

There is a way, w3m-emacs does it. If I understand your question you
want an option available on w3m:

T runs the command w3m-toggle-inline-images
   which is an interactive compiled Lisp function in `w3m'.
(w3m-toggle-inline-images &optional FORCE NO-CACHE)

Toggle the visibility of all images in the buffer.
If FORCE is non-nil, displaying images is forced.  If NO-CACHE is
non-nil, cached data will not be used.

alex