German Motorway Services

Hi All

In a week we are heading off to Germany. The plan is to spend most of this break in the black forest area and then take in a few of our favourite spots on slow treck home.

We booked a 2pm crossing on dover to dunkirk which I though would get us in aroun 5pm turns out the crossing is actually 45mins later. Anyway I doubt we will manage to travel all the way to our first planned stop somewhere around Baden Baden and will have to stop fopr the night on route. So heres my question - anyone any suggestions on the best route to take? Where to stop for the night? And are motorway services in Germany safe to overnight on?

Any suggestions for places to visit whilst there also gratefully apreciated.