that's objective, germans generally are more keen to speak with foreigners in english than french, no matter their level
It differs, in generally people either speak it there, and then do so reasonably, or they absolutely don't speak it, not a single word.
This is quite different in The Netherlands. In Amsterdam people in shops etc will often address you in English and are rather fluent, but even in the most remote villages of the Dutch countryside everyone speaks some amount of English. It may be with a very heavy accent and not fluent at all, but generally it's enough to at least have a basic conversation.
If I recall correctly, I believe Faroese might be the closest (depending on how you classify Scots).
One the closest indeed, although Frisian is technically even closer. If I'm not mistaken it's really quite close to old English, but a modern English speaker wouldn't be able to understand it at all ;)
That's important. The French tend to be happy to accommodate, but there's something about making it clear that communication is a mutual effort. If you try in French first, it indicates that you want to work with them rather than assuming that they should kowtow to your preferences.