We have stayed at the Fairmont Miramar almost yearly for the the last few years. We travel frequently with our 3 young boys (ages 3, 6 and 8) and this hotel's ability to accommodate kids in a friendly, gracious manner is largely unparalleled. The staff are friendly and professional but give you enough space. Items requested are brought to your room in advance of your stay, or all together, so that you do not have an endless procession of staff knocking on your door when you arrive. The concierge is also good and booked a well-priced rental car for us and nice transportation from the airport without any rigamarole.
We have stayed both in the main hotel and the bungalows and like both. The bungalow option offers a smaller room but a better location so I much prefer it. The rooms are decorated classically but are very nice and clean. The Fig restaurant has a delicious (though a little pricey) breakfast. There is also a Starbucks a short walk away for a cheaper breakfast alternative. The pool is beautiful and is a big hit with the kids and it also offers a good poolside menu.
In terms of location, the hotel is close enough to LAX (about a 15 minute drive) and is a short walk to shopping on the 3rd street promenade and to the Santa Monica Pier and beach. I like to run in the morning and having the board walk so close is a definite plus.
There are few drawbacks to the hotel though the parking is pricey (though it is similar to other city hotels). If not a President's Club member you have to pay for wifi but membership is free so why not. We have yet to find good family restaurant for dinner though we may not be looking in the right place. Finally, this time when I called I was quoted a price $200 more expensive/ night than when my husband called so I would suggest multiple attempts to book a room if you do not like the price you get the first round through (especially with 3 or more kids as you get charged what appears to be an arbitrary premium at most hotels). It is an expensive hotel so a little leg work may make a big difference in your bill.