A couple of thoughts, mainly re. option b, although I can't answer all of your questions...
Completing your PPL in the USA is possible. If you've alerady started in the UK, the best thing to do is to go onto the CAA's website and find the list of approved flying schools. There are a couple of UK CAA-approved schools in the USA, who will be able to get you a UK JAR license, without you loosing credit for any hours you've done in the UK (I gather, from your post, that you've already started your PPL over here, but not finished it yet?)
As for ground-school, if you can afford to study full-time on a residential course, do it. Bristol distance learning is superb - I'm half way through the course myself. It's ideal for anyone who needs to study in their spare time while working full-time (or part-time) in another job. But it's very hard work, and if you can afford to go somewhere like Oxford and study full time, you'll make things much easier for yourself. You can do these full-time groundschool courses without having to sign up to the full integrated ATPL(f) course.
Hope that helps. Good luck!
FFF
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