Jill, I too am new to the site, but I grew up in coastal SC, and have been through a few of them, including Hugo n 1989.
You're wise to be asking the questions now. One thing I've learned is that, as the storm gets closer, the fear factor goes up exponentially, and the resultant exodus from coastal areas can be an ordeal to be caught in...If Isabel makes landfall, it probably won't be before thursday or Friday, so you've got some time. But,with the dogs and all, I wouldn't wait until wednesday to leave. Just stay up with the track projections, which, these days, are usually pretty accurate, and plan accordingly. If they're projecting Jax, head for Miami, or somewhere on the east coast, no further north than Tampa. If it's headed for central Florida, then you might want to have a rainy visit to Savannah, or Augusta. Point is, if they're calling "Your number", it's way good to assume they're right and get out of Dodge ahead of the rush. Worst that will have happened is that you blew some bucks on a weekend away from home. You should also find out what's required to get back into your home area, after the storm...hope this helps..