Camping des Quatre Vents or International de Jablines are usually the recommended sites for Disney, but La Croix du Vieux Pont near Soissons is worth considering too. It's a big site with plenty going on for all ages, and runs coach trips to Disney too.
You'll find the journey easy compared to towing in England. The first time you drive it takes about 10 minutes before you feel 'at home' and thereafter you just need to be extra careful when coming out of junctions, or fuel stations, or when going around roundabouts. Just remember 'Keep your bum in the gutter' and you'll be fine! Generally the roads in France are much less crowded than here in Britain, there are many more 'caravan friendly' places to stop, and most towns of any size have by-passes. One thing to take into consideration is that off the autoroutes, try and fill up with fuel when you don't have the caravan on the back - some service stations, particularly those in supermarkets, have very narrow exits to the cash booth.
Signposting is different in France. On the autoroutes the next junction usually appears on the sign, under the current junction name - and on the N roads there are signposts directly on the junction, rather than before as we're used to. In towns if you don't see the sign you're looking for then follow 'Toutes Directions' until you see the correct sign.