It is simply a time for fun, and I think being a Christian and celebrating Halloween are not mutually exclusive. The roots of it may be Pagan, but so are many, many other holidays we celebrate. There will always be people who complain for religious reasons and don't let their kids do it. They should make it up to them at some other time. Yes, I think it should be.
Kids really look forward to dressing up.
I remember my grade school would have all the kids parade through the lunch room so that everyone could see the costumes. I still have some of the pictures and they bring back fond memories. Hi GF, sorry BB didn't hit a homerun today. Halloween is a fun holiday. Hence, that's why parents should chaperone their children when they trick or treat.