wrt54gl Ports Open?

I flased my WRT54GL to the v23 sp1 of dd-wrt and after a few days did a port scan on it using "shields up". The port scan showed that all but three ports were closed (not stealthed) and the other three were stealthed. Are all of them supposed to be stealthed and if so how do I do this? This is the default configuration outside of setting up the wireless connection settings.

Thanks!