Holy Ghost doesn’t just have a Catholic ethos - it’s a Catholic school and unless your children are baptised Catholics and you attend Mass regularly I’m not sure you have much chance of getting in (it’s very small). As for the other two, it probably depends on where you live (Honeywell is notorious for having a tiny catchment area although things may have improved now the birth rate has gone down) - Belleville is bigger. Honeywell doesn’t have a uniform. Hopefully someone with a bit more up to date experience can give you a more enlightened answer