All these steps are optional. If you plan to use Virtual Bugzilla in production environment, most steps are highly recommended.
Log in as root, and do passwd root and passwd bugzilla.
Don't forget to change urlbase parameter in Bugzilla.
The initial administrative account for Bugzilla is admin/admin, for the sake of simplicity. The username should probably be changed to your e-mail, and password should be changed to something more secure.
Edit /etc/mysql/my.cnf and uncomment (remove "#" character) the line saying bind-address=127.0.0.1. Restart MySQL with /etc/init.d/mysql restart.
Edit Bugzilla mail parameters and set mail_delivery_method to SMTP and smtpserver to your local server for outgoing mail. Set mailfrom to be a valid e-mail address.
Alternatively, you can change the configuration of the exim4 MTA included with Virtual Bugzilla. Log in as root, and run dpkg-reconfigure exim4-config.
Look into setting good values for: maintainer, timezone, upgrade_notification.
It's easy with VMWare - you can periodically make a copy of the whole VM. You can also use shadow database support in Bugzilla.