Hi Ann!
When planning a Walt Disney World vacation, I think the most important questions are:
1) When are you going?
2) How long are you staying?
3) How are you going to get there?
4) Where are you staying?
5) What are your plans with respect to dining?
You need to keep your budget in mind when answering these questions. Everything else will fall into place and is not so critical. So it sounds like you have the most critical questions about answered. I would suggest you think about dining and especially whether you would like to eat in table service restaurants; its a good idea to make an
Advanced Dining Reservation (ADR) for them and during the busy times of the year it's almost mandatory. ADRs can be made up to 180 days in advance; I know that sounds crazy but Walt Disney World has some amazing places to eat at and some of them are very popular, filling up months in advance!
With two children ages 8 and 10, I suggest you focus on the Magic Kingdom (MK), Hollywood Studios, Epcot and Animal Kingdom in that order. You can view the park hours under "Plan" on the main
WDW web page for the dates you have in mind. If you are staying in a WDW hotel, then you will have access to Extra Magic Hours. Knowing the park hours for the days you are visiting may suggest a certain order in visiting them. I would start off planning at least 1 day for each park, but know that you can't see everything in a day! Epcot definitely requires 2 days! If it seems like it doesn't matter, then I suggest visiting the MK first as it is the crown jewel of the Walt Disney World resort. Once you have a basic idea of which park you will be visiting on a given day, you can make ADRs for those restaurants you are interested in.
Enjoy planning your vacation and write back if you have any more questions!