There is a list of things that bother everyone not just the senior members here, but internet posters everywhere, in the forum guidelines.
All of the things Goober mentioned are covered there in one way or another.
We really can only go so far in preventing stupidity, while a big red "do a search" line might help it is up to all posters to read the guidelines, if the opportunity to read the guidelines is given prior to registration (and I do believe it is) and the guidelines are not followed then the necessary steps to maintain board standards will be taken.
This includes, but is not limited to, progressive discipline (a novel feature, unique to our site you will find) an online "beasting" (really common, everywhere on all internet forums) deletion of posts/topics/polls and offensive profile material.
The idea of "free speech" is a privilege on this site as it is privately owned and operated, so the charter of rights and freedoms does not apply, unfair perhaps (not in my opinion) but as I said it is a private forum (with great liberties given out) so it's not as though one can appeal to a higher power about.
Take it on the chin and push on, learn from other posters' mistakes as well as your own.(Not anyone in particular, but a general 'your')