Allyson,
While it is impossible to know what park will have Extra Magic Hours when (for sure), there is one certain thing you can take for granted. Starting the first Saturday of your vacation (Day 3) you will face some pretty large crowds. So I would make sure that you get as much done on your arrival day and that Friday, when crowds will actually be very light.
- November 18 - Magic Kingdom
- November 19 - Magic Kingdom
- November 20 - Hollywood Studios
- November 21 - Epcot
- November 22 - Park of Choice
- November 23 - Animal Kingdom
- November 24 - Magic Kingdom
- November 25 - Departure Day
I would leave the 22nd open to whatever of the two parks, Hollywood Studios or Epcot, that most appeals to your party after the 20th and 21st.
Also, make sure you plan out any table service restaurants, and make Advanced Dining Reservations well ahead of time. Table restaurants get very booked up at this time, and you want to be sure to get in your planned meals.
Write me back when the November dates are up (probably in early May), and we can make sure the plan still is the best for your group!
Have a magical vacation!