Try visiting the email website and deleting them out of your inbox there. Or move them to a folder if you don't want to delete them.
Then go into Settings > Mail, Contacts, Calendars and select your account. Turn off the Mail. Open Mail to make sure the emails go away, then go back to Settings and turn your Mail on again.
If you don't have an on/off switch for mail (I don't use AOL so I can't be sure), delete and re-add the account instead of turning it on/off.