When I toured Normandy in 1999, my patchy French was enough to get by, and was necessary.
But when we went in 2006, there was a lot more effort to speak English with me although by then my French had much improved. You'll get by. If you want to learn any French, stick to learning your way around a French menu, though many are French/English.
You've already done your homework, that's great. Look at what you can do:
- Arromanches (wreckage of the mulberries still encircle the bay, museum okay, village delightful)
- Drive up the coast to Utah Beach, don't miss the splendid little museum in Ste. Mere Eglise and the film shown in the Musee on Utah Beach...lunch at the cafe just across the way
- Pointe du Hoc (though in 2006 the actual point monument (the Reagan speech) was closed)
- Colleville-Vierville with the cemetary and Omaha Beach (walk down to the beach from the cemetary, beware of wild boar)
- Caen Museum (the original WWII wing is wonderful, just skip the new Cold War wing unless you fancy shabby moral equivocations
- Bayeux Tapestries
- Ouistreham
- There's a fine little museum in a German gun tower to the westerly end of the Norman coast, can't remember the village
- Pegasus Bridge and Museum
Do you see now how engrossing your trip can be if you take it at your own time? Rent a car at Charles de Gaulle and drive right round the Paris beltway and straight out to the coast.