January 2, 2006 is a Monday, and yes it's a national holiday.
There are really two questions here. One is are you going to get to Orlando on the 2nd, the other is what happens to the reservation if you don't.
The reservation question you already have the correct answer to, from Carol. If you are having flight difficulties to the point that you fear you may not make it to Orlando...definitely call the resort. The resort -- not Member Services.
With the flight, it's hard to say because we don't know what airline you're flying, or where you are flying from. If you are flying from Logan, you will have more options than from Providence.
Airlines overbook flights, so if there are cancellations, you should get a seat. You should know, however - before you book a standby ticket - that the airline is going to fulfill their frequent flyers' standby requests before yours. Personally, I don't think there will be a lot of heavy-duty frequent fliers flying on Jan 2, but you never know.
If you don't get on your scheduled flight, they will try to put you on a later flight. If you're flying a major airline, they will obviously have more flight options to use to try to accommodate your standby. If you're flying Wing 'N A Prayer Airline, they may not have another flight that day.