you'd need to clear out USER_PROFILE too (parallel as implied by your join)
also, you prolly want to remove them from the USER_GROUPS table, the ONLINE table, USER_DATA, RATINGS, DISPLAY_NAMES, WATCH_LISTS, PROFILE_COMMENTS, CALENDAR_EVENTS
soooo, i'd just really recommend you search for all users with posts 0 in the Admin cPanel and delete em all from there.. it does a chunk of 20 or so at a time, so even if you have a timeout, it can be restarted..
your call
