[Excessum]

Hmm... i've always seen General discussions as a lightning rod (make it spam rod) of JF. So that people who are having an urge to post, but have nothing to say on any of the J-related topics could express themselves there instead of contaminating the main JF boards.
Closing it would be like cutting off the lightning rod and hoping for the best when the storm comes.
So, instead of going the easy, hasty and dangerous way, i propose a compromise.

1) Put the responsibility of the thread contents on the shoulders of it's creator by allowing him to edit the contents of his thread in the General discussion section. If a mod sees that the thread has gone off-topic and the only thing that is going on in there is spamming/flaming/chatting he can just close the thread without editing every single bad post and then let the creator of the thread clean it up, making him follow up on his creation. Thus the creators will be forced to follow up and keep their threads sober.
2) Make the rules regarding general discussions tighter, disallowing creation of completely unwanted types of threads.
3) Disallowing the new (below n quantity of posts, account younger then 2 months etc.) members to use general discussion, in order to discourage them in staying in JF if they are not interested in the main sections of this forum.

Disallowing something completely will not answer the problem, it will cause even more problems in the long run.