How to get rid of the girandole

Each time I click a forum’s thread (or any other ROOT page), the first thing I need to do is to “scroll down”.
Well, I simply got tired of scrolling down (more than 1/5-th of my window is wasted by that girandole).

And if anyone could tell me how to enforce my own “style” upon ROOT related pages, I would also be grateful if I was able to enforce the width of ROOT pages, so that I don’t need to scroll right, each time I want to read the whole line. Well I’ve already tried to talk about it but without much luck:
[url]Forum problems

Also, It would be nice if I was able to get rid of the left part of the display of the forum’s posts -> that one which shows the author of the post, a picture, the “Joined:…” field -> this also wastes about 1/4-th of the available space (in horizontal direction).

Maybe someone knows any way to force Firefox to use my versions of some “style” files each time it tries to get them from any ROOT web page?