Switching resorts is easy! The day of your switch, call bell services and tell them you are checking out of, let's say Port Orleans and switching to Animal Kingdom Lodge. Bell services will get your bags and move them to the new resort for you. You'll have to call bell services at the new resort when you get settled in your room and they'll bring up your bags. We did this in December from AKL to the GF. The staff at AKL was great! Very prompt and no problems at all with "hopping" from AKL to GF.
Have fun!!!!!!