Hello there!
Just saw your ptr as I was browsing about because I am in the process of planning my families first trip to the world. We have been to DL many times, stayed both onsite and off and have booked with packages and without. We have taken the shuttle and have rented cars.
Have you made your way over to the Disneyland board yet? There are some really great tips over there. If you are not dead set on staying at the Fairfield, you may want to consider The HOJO. It is a favorite with many on the board. My family has stayed there 3 times and love it. It is right across the corner street from Fairfield, but actually more convenient to crosswalk by MIMI's if you like to cross there. (we do as it is much less crowded) They have a pirate themed splash pool area as well as a large garden pool that is lovely to swim in all year round and also has a great view of the fireworks. The best part of the HOJO is that the rooms are huge. Seriously, the largest hotel rooms I have ever stayed in. Their rates are also pretty good. They offer a 15% discount if you mention the disboards, they offer 50% off with an entertainment card (although not likely the week you are going).
http://www.hojoanaheim.com/
They have a forum
http://www.boards.hojoanaheim.com/
They do have two suites.
http://www.boards.hojoanaheim.com/viewtopic.php?f=50&t=9
http://www.boards.hojoanaheim.com/viewtopic.php?f=50&t=8
Anyhow, worth considering and it seems like the rooms usually end up around $120 after discount in the high season. The advantage of booking not as part of a package is that you will be able to rebook, or cancel at will clear up to 48 hours before the trip to take advantage of any specials that come out if bookings are down. I really like that flexibility.
Normally I book off-site, and then if the onsite hotels run a special, will switch to that if it makes sense. You can't do that if you book with a package because of the penalties.
And then you are paying a lot for a package over booking seperately. Basically if staying 6 nights, hotel cost should not exceed $800, maybe $900. Tickets are $700 for family of 3 and $500 for family of two.
Total cost booking seperately: $3000 with potential to save more and or apply additional cost to stay on-site.
Also, there is an alamo rental counter right in downtown disney. I have snagged a car there for a day for as little as $24. I have also just grabbed a 5 day rental for around $100, and then we use it for our day trips and then drop off at the airport when we go home so save the shuttle cost of the return.
You might look into that as you could get your shuttle down to $8.00 per person, booked with coupon from entertainment book, one way, then apply savings to cost of rental car. It is nice if you want to just go to a character dinner, you can drive to DLH and park for free. You can run to target for cold medicine and/or few groceries, etc. etc. Not to mention on two trips hubby has had to go to the walk in clinic and having the car was a life saver.
I would just bring your booster with you on the plane. They will check it for free.
As far as length of trip and days at parks? Well, we have been many times, yet when we planned a 9 day trip, we thought we would spend more time at beach etc. because we have been to disney so much and we ended up going all 9 days! Crazy, huh? But we love all the shows and we love the rides and just sort of enjoy really absorbing everthing in the resort. Based on your love of Disney I think you will easily enjoy 6 days. I would recommend that you consider the christmas tour also.
I will be following along and look forward to hearing about your plans. Let me know if you have any questions and I am happy to help. I have two boys, ages 15 and 9, and we started going when my youngest was almost 3.
Tracey