Here's a suggestion. Fly into MCO the day before you check into Port Orleans. Take a free shuttle to an airport hotel (we have been using Marriott Lakeside). Arrange for a large van, Mears or other, to pick you up early the next morning to take you to POR. Drop off luggage, check in (since you might be the first ones checking in that day, you should have more choice as to where the rooms are). Get your wristbands, and head to a park. Come back when the rooms are ready.
We do this everytime and it works out beautifully. It is relaxing, zero rush, no lines. And your first day is a full Disney day, not a half day or less.
Also, the van service usually includes a grocery stop, but careful if you are buying beer/wine, there are certain time restrictions on buying alcohol it might be Sunday only though.