Just an update to help any others driving to Spain for the first time.
It is enjoyable!! OK, we avoided Paris, headed for Rouen from Calais and stopped at Saran just north of Orleans as it seemed sensible to have a "gentle" introduction to European roads... Although French autoroutes are only two lanes, driving discipline is soooo much better, catch up to someone, check if safe to overtake, indicate, overtake, indicate and come back in, Repeat as necessary....... allows continual speed limit driving with little stress..... Don't know why we didn't do it years ago.
Stayed with friends near Limoges and again near Toulouse, then drove to near Barcelona and stayed at a great hotel, cheap room but superb standard. Food and drink though took the price up steeply. Then 7 hours to Mojacar, again easy drive, just busy around Barcelona and Valencia, but no serious problems.
now, we're planning our return, mid November, so looking for a sensibly priced hotel and where to eat, close to E15/A7 around Barcelona, then we want to visit the Millau Viaduct and head up to say 3 hours from Calais but avoiding Paris. Should we plan to pass east or west of Paris and where is a good place to stay 2 or 3 hours from Calais?
We appreciate the help given so far, and hope to make the journey back with say two drives of 8 hours a day, plus a few more hours to Calais, 2pm ferry.
Look forward to your ideas!