For some reason, includes/db.php got a switch at the begining,
And its not even know that $dbms exists so it just doesn't include the sql_db class so it fails with an error that sql_db is not a declared class

cat mysql_schema.sql mysql_basic.sql | mysql -u [your mysql username] -p [your phpBB 2 database name]
If you have phpmyadmin you don't have to cut&paste, you just type in where you have the schema and content on your HD under 'location of text file' or hit browse. Easy, the default admin password is 'admin', couldn't see that written anywhere? Like the new admin section.