How long do you want to take over the trip? It's about 1,200 miles (depending on your ultimate destination) so that could effect the route. Also, do you want to drive on Autoroutes or secondary roads?
If you can flesh out your intentions a bit, then I can probably make some recommendations. In the meantime, have you looked at this site for accommodation on the way down -
Paradores. Whilst they do vary in quality in our experience, most of them are in interesting characterful buildings and the best are excellent.
