Closing database vulnerabilities with root account

I have set up 3 new moodle servers over the past couple weeks.  When launching phpMyAdmin, it was clear via a big warning that I needed to update the root account with a password.  This is the message prior to closing the hole.

"Your configuration file contains settings (root with no password) that correspond to the default MySQL privileged account. Your MySQL server is running with this default, is open to intrusion, and you really should fix this security hole by setting a password for user 'root'."

I tried a couple times to update the root account with a password, but I kept creating problems for myself, like this one:

MySQL said: 
#1045 - Access denied for user 'root'@'localhost' (using password: NO)

phpMyAdmin tried to connect to the MySQL server, and the server rejected the connection. You should check the host, username and password in your configuration and make sure that they correspond to the information given by the administrator of the MySQL server.

"

UPDATE config.inc.php

After you add a password for the root account, ensure you add the password to the phpmyadmin configuration file, SO YOU CAN STILL ACCESS phpMyAdmin.  The configuration file in my environment is located  wamp\apps\phpmyadmin3.5.1\.

Update the user connecting from config.php

Do NOT USE ROOT ACCOUNT to connect from config.php.  In phpMyAdmin, create a new user from the User menu, assign the user a password and minimum privileges necessary.  Ensure you specify the Host name in your new user record.  I had trouble with this and was only able to use 'localhost', no wildcards '%'. 
Test the new account in one moodle instance, once its connecting, update the other instances.

Defining privileges was very tricky/confusing. The Host property would only work when i used 127.0.0.1 or localhost, but not any combination of a %, which is supposed to be global or mean applicable anywhere.  I admit I am not a phpMyAdmin guru, but I found the interface very confusing.  Why are there 3 different root accounts and why can't I edit the account detail / privileges in one interface?

I did return a day later and modified the privileges on the new user account created.  I was unable to restore a course until adding some structural privileges.

The error when trying to restore a course backup was "DDL sql execution error".  Again, this had nothing to do with the actual restore file or the sql, it was a lack of privilege on the user account connecting from config.php to the mysql db.