JBoss health monitoring

What are some best practices on ways to monitor the overall health of the container (e.g. pools, JNDI, EJBs, etc.)?

I guess I should refer you to the performance chapter of JBoss In Action. Just about everything you need to know is there, including which MBeans to monitor.

Also, the JMX Console is your friend. I suggest using it to examine the MBeans available. Yes there are a lot of them, but if you look at just a few each day, after a while you will get to know what data is available.