Anthems or ambiance, these are the tones that rattle your bones.
Every year I make a Halloween Mix C.d. for friends, family, and myself. However I have a feeling that some of the song I put on my past c.d.s don't have a Halloween feel to them. That's when I started to ask myself, "What qualifies as a Halloween Song?" A have a few that I could think of, but wanted to know what my fellow Minions had to say on the subject.
I think it has a lot to do with just sheer subject matter, i.e., ghosts, goblins, skeletons, trick or treating, monsters, etc. You don't want it too vivid or too gory, because at the root of it all Halloween music should be able to be enjoyed by everyone young and old, So I'd say no use of a parental advisory sticker... Also, minor keys are a big plus. They're dreary and give that slow, lumbering, cringey sound. It should be "delightfully spooky" rather than "pure evil". Save that kinda stuff for the adults :)
I've been building a collection of Halloween music for many years. There are of course classics, but after making countless mix CDs and playlists, you start to look for tracks beyond the usual Monster Mash and Thriller. So I've had to ask myself too - what qualifies as a "Halloween song"?

First, you can just go by the lyrics. Some songs are directly about Halloween, but in my opinion, anything with remotely spooky ideas is fair game. If I find a song that even mentions a word like "ghost" or "zombie" it gets added to my Halloween collection. This allows you to come up with a playlist with many different genres. My Halloween tunes include Classical, Country, Electronic, Funk, Rock, Pop, Surf, and many more.

Next, consider the musical style. Here I'm thinking of instrumental songs, which have no lyrics to influence you. Instead you're listening to the pure sound. Imagine some gothic ambient compositions. You know the ones I mean. It just sounds like the soundtrack to a haunted house. They might even have some creepy sound effects mixed in.

Also, sometimes a certain artist can have a strong enough association with Halloween that any of their songs become worthy of the holiday. Not every song by Alice Cooper or Rob Zombie is about ghouls, but the image of these singers is enough to make their entire albums appropriate for a Halloween party.

One other approach: Sometimes a song is used on a horror TV show or movie, and then it takes on that association to our favorite haunted holiday. For example, there was nothing spooky about Harry Belafonte's "Day-O" or "Jump in the Line" until they were used on the Beetlejuice soundtrack. Now they're part of my Halloween music collection.
I actually have something known as a Halloween playlist! It has all sorts of songs like Highway to Hell (AC/DC), Creep (Radiohead), Werewolves of London (Warren Zevon), Ghostbusters (Ray Parker Jr.) and of course Michael Jackson's Thriller.
I plant speakers throughout the yard playing scary sounds but also include 4-5 songs from Harry Potter. Kids recognize and associate with Halloween so it works.
I know a few good songs that are halloweeny without being over the top

For Zombie Dance, it's important to keep in mind that someone sped up the song and changed the pitch
hmmm I'm not sure what qualifies - but my husband and I both consider "Everybody" by the Backstreet Boys (and really, I am not a boy band fan at all) a Halloween song - because of the video. We loooove the video