Hi,
Go to allears.net. Awesome unofficial site for all things Disney. Great info on hotels and pictures of them you cannot find elsewhere. They have a part that tells you crowds are at highest and lowest. I do think any holiday time is crowded. If you can take the kids out of school on an off time that is ideal. We have done that w great success. We stayed at Caribbean a few years ago and it was pretty nice. I have heard that Port Orleans is the best of the moderate resorts. Although Caribbean just added pirate rooms and a themed pool if you have little boys.
We stayed at the polynesian last year. It was so-so as it is a bit dated...yes, it is on the monorail, yet that is not a huge selling point for me. We go to one park a day and do not go back and forth so I do not mind even staying off property. We stayed at the Ritz Carlton, which you cannot beat. The only thing with the hotels on property is that sometimes it is a little walk and a wait for buses. But again, if you are going once in the morning and back to the hotel, it is really not a big deal. The food choices are a little limited at the moderates as well...but if you are ok with a food court then I think it will be great. I always call liberty travel for pricing because I have gotten some good deals from there.
I just love Disney! Have a great time!
Also, we have gone at different times of the year and the weather is so hit or miss in the fall/winter. I looked for a hotel with an indoor pool but could not find one. It did not stop my so from swimming in 60 degree weather. Anything beats the summer heat in Florida!