How many usergroups do you have? You should only have to do this once for each usergroup (unless you went and changed it for every single forum for each usergroup).
You may want to ask this over on vb.com. They do have this thread - Updating Options En Masse with Queries - but I don't see the queries you want in the list.
Then i hop you won't get any more members. A setup like this wil, especially if you also use a lot of forums, quickly eat up the memory of even powerfull servers.