To Norway from Germany: Road trip or via plane?

Thank you all for your tips! Proved most helpful while planning. As a consequence, we kept our attention focused on the south, and did Oslo, Telemark, Stavanger and Kristiansand. The landscape was spectacular, and driving across the country is surely worth the effort, allowing one to get off the beaten track, and explore via the smaller 'old' roads away from the rush of the 'European Roads'.