Re: Two different databases
Separate db vs one table is something new for 0.9 I believe.
Those are constants that have to be defined in bb-config.php just like any of the other constants. ie.
If you are just now installing bbpress and not already integrating an existing install, if you wait for the 0.9 release on monday, it will do most of the integration for you.
There are endless instructions for integration, I’ve gathered most of them here (though that list is getting outdated for 0.9)