MouseSavers.com - go there. Read it, know it, live it.
In answer to your question, the best thing to do is book directly through Disney. I can't remember which one does, but most of those discount travel sites do not do on-site Disney (I know at least one does...).
If you book yourself through Disney, you have the power to call and change ressies/etc. at any time. I highly reccomend that if you think you will be applying a discount code later to NOT book online. If you book "in person" over the phone whatever deposit you put down can be picked up and applied to another resservation very easily. I did this my last trip - I booked the room as soon as I had my dates, and waited for the right code to come up. My initial deposit was higher of course (equal to one nights accomodation), and that's where I ran into a snafu.
When you book online, you CANNOT change your ressie without actually cancelling it. This meant that they couldn't just transfer the money they took off my credit card for the more expensive ressie and just apply it to the new one - I had to be refunded the initial deposit and make a brand new one.
I also had a problem with getting that refund which I detailed in a thread here - it took several calls and a couple of weeks to get my money back for the cancelled ressie (they even lost the refund at one point).
However, any time I have just called and booked over the phone it's painless - they have a lot more power to change things than with online ressies. Plus, you can still pay by check if you desire, which gives you two weeks to make the deposit which can be helpful as well.
AEfx
