Hi,
You can unsubscribe your user in two ways. By editing the user and unsubscribing him or edit your list and scroll down to your subscribers. You'll find a unsubscribe link at the end of each row.
To actually delete a user go to Acymailing->users. Place checkmarks in front of the users you want to delete. As soon as you have placed at least one checkmark the delete option in the dropdwon on top of your list becomes available.
