Installing Drupal

Hi. After creating two new sites, but before installing the database, I modify settings.php:
$databases['default']['default'] = array(
'driver' => 'mysql',
'database' => 'bikes',
'username' => 'my-user-name',
'password' => 'my-password',
'host' => 'localhost',
'prefix' => array(
'default' => 'mountainbikes_',
'users' => 'shared_',
'sessions' => 'shared_',
'role' => 'shared_',
'authmap' => 'shared_',
),
);

$db_prefix = array(
'default' => 'mountainbikes_',
'users' => 'shared_',
'sessions' => 'shared_',
'role' => 'shared_',
'authmap' => 'shared_',
);
...for a site named mountainbikes and a second site called roadbikes. The above is for mountainbikes, I change the two instances of 'mountainbikes' to 'roadbikes' for the other site. I then create the database as follows:
> drop database bikes;create database bikes;show databases;
and I see the empty bikes database created (and I confirm its empty).

When I restored local db to remote server it all worked fine but now I am attempting to do it from one server to another can I change database name to something without underscore as was configured by cpanel eg mydb_name.sql and change it to newname.sql and just reflect that in settings and conf?

I am getting an error when I change the permissions on the settings.php file JUST after installation. The error shows the Install screen and says "Select and installation profile", with this error:

"Warning: include_once(/var/www/vhosts/girlzone.com/httpdocs/sites/default/settings.php): failed to open stream: Permission denied in drupal_settings_initialize() (line 712 of /var/www/vhosts/girlzone.com/httpdocs/includes/bootstrap.inc)."

Hi,
I hope this is the right place to post, I have read several similar posts but none seem to get at exactly what I want to do.

Bound to CentOS I'm following the Aegir install guide @http://community.aegirproject.org/node/389

It fails when trying to install the right Drush version (4.6.0). Because Drush 5.x isnt working with Aegir.
Commands are:
pear channel-discover pear.drush.org
pear install drush/drush-4.6.0

I read the documentation at http://drupal.org/node/238805
for local machine set up with multi sites and found it interesting two settings.php were placed in each site folder under sites.