Arliani,
I do not have personal experience with requests related to halal, but I do have a recommendation. I have known MANY people traveling to Walt Disney World with very specific dietary needs and requests. From food allergies, to personal dietary preferences, to requests like yours, I can guarantee to you that they take your needs
VERY SERIOUSLY!
I recommend you pick the first table service restaurant where you are dining. Call that restaurant and ask for a member of the chef staff, indicating that you have a special dietary need. You may have to explain to them the intricacies of halal food, in particular the source of the food, and probably also the nature of how some of the proteins were slaughtered.
They can often identify appropriate menu items, and even assist in letting your other restaurants know (very helpful!).
Also you might download the menus. Many are available now on the Walt Disney World website of each restaurant, but you can also get them from the dining section of
www.allears.net.
Please send me any follow-up questions on this, and I will see what else I can do to help.
Have a magical (and delicious) vacation!