I want to know if there's a way to make certain enemies immune to a large number of status effects (like bosses) without having to fill up the entire parameter box with putting in every single status the enemy is immune to. Is there a way to do this without a script? If it does require a script to do, does such a script exist? Any help is appreciated.

You could use Yanfly's passive states script.
Then you would need to make a state called Immunity that would give the enemy immunity to whatever states you want,

then in the enemy's notes box just put <passive state: x> and replace x with your immunity state.

Link to script
http://yanflychannel.wordpress.com/rmvxa/g...passive-states/