The word "Halloween" means "All Hallows Eve" which is old English for the Vigil of All Saints Day which used to be listed on the calendar before the reform of Pope Pius XII in 1955.
So in answer to your question the answer is a resounding yes!!! Halloween is a very Catholic holiday.
 

I'm confused because culturally I never saw anything wrong with Halloween. It was a pretty big holiday when I was a kid. In Brazil it has a bad rap because in Portuguese it is called "the day of the witches" and it's looked down upon. My wife seems to be fully convinced that it is demonic.  I had to explain it a little at work...etc.  

Then I see articles like "Halloween is Catholic" etc.

Basically, I just want to see it from everyone's point of view to see if I form a different opinion.  

The Feast of All Souls
As poche pointed out, the 31st of October is the Vigil of All Saints (Hallow means saint, coming from Middle English 'halwe', cf. German Heilige). All Saints (Nov. 1st) is the feast of the Church Triumphant in Heaven, All Souls (Nov 2nd) is the feast (if I may use the term) of the Church Suffering in Purgatory.

From the Catholic Encyclopedia : The Office of the Dead must be recited by the clergy and all the Masses are to be of Requiem, except one of the current feast, where this is of obligation.

Pope Benedict XV granted priests permission to offer three Masses on All Soul's Day.  One of these Masses the Celebrant may say according to his own intention; one must be offered for the faithful departed and the third for the intention of the Holy Father.

The Raccolta gives the immeasurable privilege of a plenary indulgence applicable only to the Holy Souls, toties quoties to all who devoutly visit a Benedictine Church or, if because of infirmity or distance, greater than a mile, you can't visit a Benedictine Church, wearing a blessed medal of St Benedict, visit any Church, from the Vespers of November 1st to sunset on November 2nd. I can see no reason why not to go in and out of the Church as often as ever you can. You could obtain many plenary indulgences on a single day.

The Raccolta itself gives the conditions:
https://archive.org/details/theraccoltaorcol00unknuoft

Customs
On the Continent [of Europe], the laudable-seeming custom of tidying up relatives' graves, bringing candles and flowers and saying prayers for the Dead is observed on Nov. 2nd. I can understand the Breton custom of washing the grave

Soul-cakes were once given to the poor as alms, the merit of the act being applied to the Souls in Purgatory.

The dressing up as demons, ghosts, witches  (I remember listening to an interesting tape by an elderly Jesuit who pointed out that a ghost may be one of two things -- a soul in Purgatory permitted to appear on Earth to ask for succour or else a demon. If it's malicious, then it's a demon as they're Holy Souls. The best thing to do is have a Mass said for it. If it's a holy soul, it will do it good. No demon wants a Mass said!) and so on, divination, horror stories, carved pumpkins and the rest of it strikes me as thoroughly pagan, glorifying the occult, and to be avoided. So, too, trick-or-treating, guising and the like.

The custom of souling, or going from door to door begging cakes in exchange for prayers for the dead, seems to have degenerated into trick-or-treating.

Summary

To my mind, avoid ''Halloween'' utterly. The disgusting parades of witches, murderers, demons and the like are in no sense Christian and have nothing to do with the Holy Souls. Take your children to church on All Souls Day to pray for the dead and above all to obtain the precious graces our Mother offers us for the dead.

I am not a priest, but it seems an open-and-shut case to me. A holy feast has degenerated into occultism, perhaps by connection with the pagan Samhain.

Halloween has its roots in the Catholic liturgical calendar.  It started out as being the vigil of All Saints Day.  

Is it, today, a Catholic holiday?  I can only answer for the celebration of Halloween in the United States.

In the United States, Halloween used to be a fairly benign celebration involving pranks, candy, etc.  My mother related what used to happen in her hometown in Iowa in the 1920s and 1930s.  The town's kids used to remove all the gates from the picket fences around the town and put them in nearby bushes and trees.  The next day (this is in a pretty much non-Catholic town and my mother was not a Catholic in her youth), the fathers would pick up the one or two gates on their property and take them to the town square where everyone would look for his gate and take it back home and put it back on the fence.  

Through the 1950s and 1960s, it transformed more into a day to dress up in haunting costumes and go "trick-of-treating" in which the pranks formerly done were now suspended because the homeowners would give candy to the kids.

This is still done, but it has taken on a very serious demonic and pagan aspect for a huge part of the population.  Halloween, as such, is certainly not a Catholic holiday anymore.  For many people, it is much more significant that even Christmas.  Retailers are certainly trying to make Halloween at least as big as Christmas to increase sales.

Sorry, some corrections: I can understand the Breton custom of washing the grave with holy water but the pouring of milk on the grave strikes me as a pagan abuse.

I'm inclined to say that the All Soul Day Customs are laudable, not merely laudable-seeming. I am rather scrupulous feared a vestige of paganism but I simply can't see it.

As to gargoyles and skulls, they are holy, laudable and good. The polish chapel is a good shock to the spiritual system, if I may say. Very edifying, as well as provoking compassion for the Holy Souls. I could also point to the ossuaries of the friars in Rome and Austria.

Remember, Man, that thou art dust, and unto dust thou shalt return is a holy thing to keep before our eyes. Hence the crosses on Ash Wednesday. It's an excellent preventative of sin to think that I may very well not get through today alive but may be before the judgement-seat of God.

However, excepting the old mystery-plays, which again have a devout purpose, I cannot see any reason that is good to be going around dressed as a demon, and never as a witch, Death, or so on. I don't believe for an instant that it makes people think of their last end and if it does, it tends rather to encourage debauchery (life is short) than holy fear. The connection with Samhain in the press, the tendency for debauched parties, the utter lack of reverence for the Holy Souls, all point to a pagan ceremony.

I fear I sound a little arrogant. I am most sorry,

God bless you.

The villainization of Halloween is rooted in protestantism, largely for the very reason that Halloween is Catholic in origin.

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Images reminiscent of Halloween costumes
in Los Angeles* (where Hollywood is)...

*the images below are not all from L.A., but are available worldwide on the Internet




Crack addicts, before and after
(could be before and after Halloween makeup):











How many crack addicts would get caught up in crack to begin with if they could only know in advance what the addiction would do to their appearance?

These pictures can be helpful for us to think about what sin does to our souls.

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By all means celebrate Halloween, but keep it Catholic. Visit a graveyard, pray for the dead. Let the kids dress up as saints and other historical figures, animals, benign mythological creatures, or even souls in Purgatory. Visit a farm that has a corn maze, hay rides, story-tellers, or other harvest-oriented amusements. (You can do your own research on local traditions.) But separate yourself from any tinge of gluttony and hedonism, child or teen misbehaviour, consumeristic Mammonism, and witchcraft or downright Satanism.

This is my position as well.

Someone made a good point -- all the fundamentalist protestants that say "Halloween is evil" aren't inclined to hold back at all, considering that Halloween was formerly a Catholic holiday (All Hallows Eve). They don't believe in getting intercession from the Saints, they don't believe in praying for the Poor Souls, they don't believe in purgatory, etc.

Now joining in the trick-or-treating is problematic, because of what all they'll see on their trip -- the bad stuff (witches, satanism, horror, evil, vampires, etc.) as well as worldly spirit and immodest costumes.

I think Catholics should do SOMETHING on that day, so their kids don't feel left out of all the huge celebration. I agree that there's nothing wrong with spiders, skeletons (memento mori -- remember death), pumpkins, hay, hayrides, fall harvest theme, memento mori theme, or dressing up as saints/animals. Likewise, we should throw in some praying for the dead, and give the kids some kind of treats.

We Catholics have to recover the holiday a bit -- and basically MAKE UP some of our own new customs, since most of us don't have a ready template to copy from. My family just trick-or-treated when I was little.

Here is a good story to read your older kids:
http://www.chantcd.com/anne_soul_hell.htm