I don't want to see everything locked... I love the Bay 12 Games forums. These are my favorite "general discussion" forums on the internet, and I enjoy the community. It's been a bit since I played DF, but that's mostly due to time and hardware.
I thought we were one of the most self-moderating communities on the internet. What other forums will have a topic veer out of control, only for a single user to say "hey, we need to chill a bit" -- and people listen? Mostly.
This. I like discussing things on these forums because, as a whole, people seem remarkably mature and open to discussion. Proper spelling and grammar are used, posts normally have content, and people are polite and respectful. While I can't say that it increase my interest in DF (since I found DF before I found the forums), I can say that having a good self-moderating community like this is a great way to bring in new people, and especially to help them over the initial difficulty hump of DF.
Having a forum where people can go and say "I tried X but all my dwarves are tantruming now, can I have help?" is good, I think we can all agree. I think we can also agree that having a forum where we can discuss mods, developments, ideas for megaprojects and challenges is also good. Since both of those require an active forum, and people aren't going to want to talk about all DF, all the time, I think that having the Finally... and Other Games sections is helpful to maintaining that active, polite, friendly community. It means that the number of people who are familiar with DF who are available to discuss DF-related things is much higher than it would be otherwise.
Strong measures against repeat offenders, though, seems like a completely reasonable step to take. There is only so much that the community can do against people disrupting the forum, beyond telling people to chill out and not feeding the trolls (both of which I think we do a reasonably good job with). Appointing moderators seems like something that wouldn't build ill-will, as long as the mods were sparing and transparent in the use of their powers. Things like explaining the reasons behind any mod action, and only taking action in serious cases where community involvement hasn't worked, go a long way towards making sure that moderators are viewed favorably.