I've found where I can set that an entire forum have all posts sent into a moderation queue (thanks Ruben) but what I really want is to have posts from only certain users sent to this moderation queue.
For instance: all users can post to the Suggestions Forum except posters A, B, and C.
To accomplish this, I tried to create a new Group called 'Trouble Makers' and I added posters A, B, and C to this group.
For this group I copied the permissions from the User group:
my-forums.Net » Control Panel » Group Management » Site Permissions
I then went to:
my-forums.Net » Control Panel » Group Management » Forum Permissions
and set "All new posts are moderated" for the Suggestions Forum.
I tried both the values 1 and -1 and in either case, posters A, B, and C are still able to post in the Suggestions Forum without their posts needing approval (going into the post queue.)
Anyone see what's going wrong here?