Cherbourg is easily accessible from Normandy and the rest of France and is around 4 h from Paris and around 7 h from Bordeaux. There is not much traffic except during rush hours. There is limited parking close to the old town and you may have to pay for it during the day.
Cherbourg can be reached from Paris St Lazare on a direct train, otherwise there are services to Brittany and to (sometimes) the southwest of France. Gare de Cherbourg is about 5 minutes' walk from the old town. It is also close to some hotels and a Carrefour but it is difficult to find food near the station.
A decent enough network of buses runs round the town, but everything can be reached by foot
There are numerous restaurants in the streets and squares of the old town and along the quay.
Phare de Gatteville is located at the north-east point of the Cotentin, about 20 minutes drive from Cherbourg. It is a lovely, peaceful spot, surrounded by fields and villages. For a few euro, you can climb the 349 steps for some incredible views.