I would probably go the Protestant line too. My girls go to a private Christian school that is a lot more easy going than the one near you sounds in that they accept families who are not practising Christians - which is certainly us - but it is still pretty full on. The kids pray multiple times a day (ie before recess, lunch etc), and there is lots of thanking of God and God bless you's going on. I must admit that DH and I do struggle a little with the religious side of it because it is far more full on than we imagined it would be, even for kindy and pre-primary. We accept that we need to support it (and we do), but do get a little bit of a laugh sometimes at the things the girls come out with - they take things so literally at this point so its pretty funny when they tell you that God is opening the door for us at the supermarket!!

I doubt you would get this level of religion in a public school, even choosing the Catholic stream, but the Protestant stream may be a smidge more balanced and open to discussion of other religions.