Go to http://localhost:8080/jmx-console, find the Hypersonic sercice MBean (service=Hypersonic), click on it and then invoke the startDatabaseManager() operation. This will open a basic GUI interface on your server to manage the HSQL database.
It seems you have been following the example from Chapter 7 "Databases and Portal". Do you know how to create the folder structure and which files go where? after creating the database table, how to create the files and deploy the war inside jboss portal server?