Here is the status update.
We are now on the latest version of the UBB forum software.
We're on the latest version of PHP, the language this software is written in.
We're on the latest version of MySQL, the database the posts is stored in.
I've added FastCGI which is an accelerator.
In general the boards seem much faster. I've added debug information at the very bottom of each page and it's showing that, in general, a page takes under a half second to draw. So that's good.
The remaining issue seems to be making new posts. It seems that occasionally the act of making a new post causes a lock-up situation that then times out after 90 seconds. The post does get made. But the user sees a "time out" error and has to manually go back to the forums.
I'm working on that now. Our post table is fairly large, but even so we should be able to add to it without it locking
Hopefully I can get this resolved shortly!