Hello Theresa!
Disney Dining Plans can really be a money-saver for many families. It can also make your vacation a little easier to budget for, since your meals are taken care of in advance. You only need to budget for gratuities for your Table Service meals (and for incidentals like extra snacks or a meal). My suggestion is to look over the different plans offered and decide which, if any, are best for your family.
If you chose the Disney Dining Plan which includes Table Service meals, you'll definitely want to make Advanced Dining Reservations. These can be made
online or by calling 407-WDW-DINE up to 180 days prior to your arrival date. Many popular restaurants will book up right at the 180-day mark, so you definitely want to make your reservations asap.
Quick-Service dining does not require reservations. QS meals at Walt Disney World are not all chicken tenders and fries! There's a huge variety to choose from. You can get everything from a Lobster Roll to Moroccan food to delicious BBQ. There's a great Quick-Service Dining Plan for those families who want more flexibility in their dining times.
As for allergies, you can rest easy knowing the chefs at Walt Disney World will take the time to ensure your allergy needs are met. You can make a note on any TS reservation about the allergy and your server will make sure you're able to talk to the chef to ensure your meal is free of any allergens. At QS locations, simply let the Cast Member at the register know you need to speak with someone regarding allergies and a manager or chef will go over your options with you.
Please let me know if you have any other questions.
Pixie Dust,
Ashley