In reply to ChrisJD:
Very many thanks, Chris, especially for your generous offer, it's really kind of you. Unfortunately, I'm about 3 hours from the Peak, but I have someone local who has just made a similar offer.
When you say the problem's not with LR, I'm not sure I quite understand. (And btw, the images on Dropbox were meant to be illustrative of the "problem" rather than of any grain of photographic ability I might have!)
I accept that shooting with a middle-of-the-road camera in poor light conditions with 25kgs on my back whilst it's windy and I'm breathing heavily isn't going to produce technically perfect images. And I welcome the fact that I can tweak the images to get them how I want; that's why I bought LR - and the G10.
I don't (yet) understand about embed JPGs and LR-default-JPGs, and that may be influencing the fact that what I'm not clear about is whether what I'm seeing after the image has "popped" in LR is the RAW image or LR's attempt to make the image look how it thinks it should. If it's the latter, then my criticism of LR is that in the case of my Iceland pictures (and some shot in the alps), I don't think it's particularly accurate.
This guy did a somewhat similar trip to us and his images 38, 47, 54, 59 and 67 will give a good idea of what the country is like:
http://www.phlumf.com/travels/iceland/photofiles/photofile47.shtml
Once again, many thanks indeed to the UKC collective. When I've got the images how they "should" (!!) look, I'll put some in my gallery. But don't hold your breath; I'm supposed to be working!