With drupal 7, password are no more encrypted through md5. There are several way to get/set a password in drupal7. Using drush (for your information, not used in your case):
drush upwd admin --password="newpassword"
Without drush, if you have a cli access to the server : (for your information, not used in your case)
cd <drupal root directory>
php scripts/password-hash.sh 'myPassword'
Now copy the resultant hash and paste it into the query:
update users set name='admin', pass='pasted_big_hash_from_above' where uid=1;