Shannara:
You cannot delete your account -- accounts are not deleted on RPoL. If changing your password is not sufficient, we can certainly lock the account for you if you no longer wish to use the site -- just send an rmail to the moderators.
Also should mention that if you do decide to do this, and later change your mind, you would need to contact us about reactivating your account, as creating a new one would be a breach of site rules.