I cant see why they wouldnt accept your family into their school parish...and even though your not religious...you will certainly be around religion should you decide to send your child to a catholic school.
We have sent our DD#1 to a catholic school - my DH nor i are religious, yet both catholics. We are surrounded by catholicism every day, my DD talks about God all the time, and was teaching my DD#2 the 'Our Father' the other day whilst they were lying in bed together....im surrounded by parents that attend church every sunday...i think if your ok to be around relgigion like this (coz after all , you are sending your child to a catholic school), then yeah, it may be the route for your child. But if that aspect bothers you, i would prob re-consider what you want out of catholic school in the first place.....

HTH