Here is a bookmarklet you can use to quickly hide the “Trending” [Tags and Topics] panel from your Facebook wall…
javascript:document.getElementById('pagelet_trending_tags_and_topics').style.display='none';void(0);
That should work in nearly all modern browsers since it uses basic JavaScript that has worked for quite some time to apply element styles.
You may also be able to right-click the following link and save it as a bookmark 😉