Add me to the "ripe" peppers camp, too! Farmerdill, I think you are the first person I've ever heard say they preferred the bell peppers green -- but to each their own, I always say!!
I do find the ones that start out white or yellow are milder than the ones that are actually green when they're "green," though...
On the other hand, for pickling hot peppers I find it's much better to use them at the "green" stage, they come out a lot crisper than once they ripen.