database problems

I admit I am new to this so be patient. lets say my login to cpanel is yyy.

When I create the database I name the database blog and the user pete
The cpanel then shows database as yyy_blog and user as yyy_pete. Is this what I use? or do I simply user blog and pete?
Here is my config file is this correct?

<?php
// ** MySQL settings ** //
define(‘DB_Name’, ‘yyy_blog’); // The name of the database
define(‘DB_USER’, ‘yyy_pete’); // Your MySQL username
define(‘DB_PASSWORD’, ‘xx’); // …and password
define(‘DB_HOST’, ‘localhost’); // 99% chance you won’t need to change this value
define(‘DB_CHARSET’, ‘utf8’);
define(‘DB_COLLATE’, ”);

on running /wordpressa/wp-admin/install.php ( my wordpress directory is named wordpressa and is a sub directory) I get the following error:
The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator, webmaster and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request
On looking at tghe error log in cpanel:
SoftException in Application.cpp:553: Directory “/home/xxxx/public_html/wordpressa/wp-admin” is writeable by others

Thanks for your assitance

Rod