I imagine you will be going to see the Bayeaux Tapestry and I would
suggest if you are pressed for time to skip the intial display explaining
each part of the tapestry. I would rent an audio guide which does an
excellent job explaining how William the Bastard became William the
There is also the Bayeux-Memorial Museum which explains a lot about the actual D- Day landing which is a easy walk from the town. If you are looking not to rent a car, Normandy tours just across from the Bayeaux train station has morning and afternoon tours for about 200 frs(at least that is what it was last year). It was a 4-5 hour of several sites including the Mullberry harbour, Omaha beach, Normandy American Cemetry, and Longues de Mer(where you see some 115mn German Guns).
When I went last June I based myself out of Caen and if you have time it is only a 20 min train ride away. There you can see Chateaux Caen and the Memorial Museum.
If you want I can send you my travelogue that I posted last year on the Travelzine or if you have any specific questions feel free to email me directly
Have a great time!
Tom, London, Canada