We began the easy way: We chose Ireland several years ago, with its similar language and food, its small geographical area comparatively, some family roots, and we had only to cope with driving on the left.
From that, we branched out to see other countries and regions in Europe, each trip some two weeks. We eat and sleep wherever, and have so far found consistently safe and clean places. We cross borders freely (no itinerary). How to find us if we disappear? We carry lots of ID, register at consulates or embassies sometimes, and email home our plans as we make them.
Side benefits: For parent-child travel, the child becomes adult, a full participant in decisions. Whether related to the trips or just Himself, Dan has developed substantial street-smarts, and is a history buff. He is an inquisitive, responsible citizen of a larger world.
See also
Europe Road Ways on the Web