What can be done within the database itself to increase performance?
Depends on what your database does but as a general rule here are some things I would look for as well as links to information you might find useful.
Create Indexes based on what query optimizer tells you.
http://www.sql-server-performance.com/optimizing_indexes.asp
What is the best strategy for monitoring the performance of a SQL Server 2000 installation?
http://www.sql-server-performance.com/tp_centralized_sql_server_monitoring.asp