My daughter's bday is around Halloween as well, and it's such a fun time to have a themed party. We always had a mix of boys and girls and she is now 11, and still remembers those parties as her favorites!
We always found it fun to have lots of games and prizes, for example we did an eyeball relay race, where the kids had a spoon with an eyeball (tennis ball or candy) and the kids had to run and exchange the eyeball into the other spoon with out dropping it. we also did the Mummy wrap which is always really fun and had a contest, who could wrap up one of the kids with toilet paper and make them into the best mummy, it's way fun if you have Dad's there and have 2 teams and a Dad end up being the Mummy on each team, the kids think it's hilarious and the Dad's get into it too, or Moms :)
Also freeze dance or musical pass the pumpkin (where you pass and then when the music stops you are out) there is another where you get a big witch pot and put prizes with paperclips on them and then take a want with a string and magnet and try to fish out a prize, (that ones good for little ones)
We also did a treasure hunt/scavenger hunt, sort of like an easter egg hunt but with the little pumpkins, and I had them decorate their own bags with stickers and markers for a craft and then did the pinata and they were able to put their candy into the bag . At each game/station we also gave the kids prizes to put in their bag.
Bobbing for apples, or taking the mini powdered sugar donuts and putting on a string and having them try to catch the donut in their mouth is another fun one.
We always have fun themed halloween music and have the kids dress up in costumes and it's always a fun time.
if you don't do costomes, face painting and tatoos are fun too.
I think boys or girls have a blast at Halloween.
Some friends of ours did a little hay ride with a 4 wheeler and pulled a trailer with haybales behind it and that's always fun for kids as well.
For crafts, painting pumpkins or decorating cookies or cupcakes with Hallween themed sprinkles is always fun too.
For other fun food ideas, you can make all kinds of cool food, like the popcorn bag hands with spider rings on them and candy corn as the finger nails, homeade rootbeer is a lot of fun and you could use a big cauldron and it just takes dried ice, rootbeer flavor, sugar and water , I'm sure you can google a recipe but if you make it in front of the kids, it has lots of smoke from the dried ice and looks really cool and spooky and it's really yummy and no caffine either!
You can also do the whole haunted food theme where they are blindfolded and you cook up spaghetti and that is the worms, and use peeled grapes for eyeballs, etc and have them taste each one and guess it.
I think whatever you do, you all the kids will love it, especially at the age 6, I would avoid really scary at age 6 for boys or girls, because you never know how scared they will get and you don't want to have to deal with a little one in tears while you are trying to have a fun party! I think the funny scary is a blast though, I know they have those mice or bats that are sticky that are sort of gross but kids love playing with them.
Good luck and hope you have a fun party!
Good luck!