Whenever I need to reset my admin password in Joomla (for some reason, it corrupts from time to time), the only solutions I see involve hacking the database entry. There is a much easier way.

In your address bar, after your domain, add /component/user/reset

Example URL: http://www.mydomain.com/component/user/reset

This will give you the page to reset your password. You will need to know the email address you used for that account.

BAM -- You are back in