1. When you add a moderator, those two options are shown on the bottom of the page. So, just set them to No before Saving. You don't need to do this for registered users, only moderators.
2. The invalid birthday message is from this bug -
http://tracker.vbulletin.com/browse/VBV-12307 (Note, you must first login to the vbulletin.com forums as a Licensed User before you may see the Jira issue.) The fix for now is to set Settings -> Options -> User Profile Options -> Require Date of Birth to No