To remove someone from the Membership Database:
Go to the Club Control Panel and click on Membership and then Membership Database.
Select the person you would like to remove from the Membership Database.
You will then see their member details.
Click into the 'Roles' tab and then click 'Remove from Club'.
You will then be presented with a warning message that looks something like this:
If you are sure you want to remove this person from the database, click OK.
Bear in mind that you can only delete users one at a time. This is for security and other reasons - but mainly to ensure that someone does not delete a large number of records by accident.