Thought I'd better come and introduce myself as I've been lurking here a while now :)
I stumbled across Poldark by accident when I was a kid and pulling a sickie from school. The BBC has open university discussions in the morning on TV and on that particular day was discussing characterisation similarities between Blakes 7, Poldark and some other series, I forget now what it was. Anyway, they showed clips of Poldark, the main ones being where Ross breaks into the Poldark house to see Elizabeth and where Francis is down in the mine and drowns. I was intrigued and eventually, when the series was repeated on TV, nagged my parents into letting me see it.
That led into reading the novels, into an interest in late 18th century history and I've loved Winston Graham's work ever since. I even tried to emulate his writing style in school writing projects, but my teachers kept correcting my sentence structure because it was (apparently!) grammatically incorrect - can you believe that! They'd obviously never read Poldark ;)
Well, that was all years ago and my memories of both books and series is a little hazy. I'll get around to re-reading and rewatching them one of these days.
Favourite characters? Well, I was a teen when I read them, so I expect I might have a change of heart when I get to reread. Also, I'm more familiar with the first six books than the later ones. Demelza was always my favourite and I especially grew to like Anghared Rhys, even though she didn't seem right for the role at first (she also appeared in another favourite TV show of mine, Robin of Sherwood, for one episode). I loved it when she got on the port ;) I remember liking Francis and the way he developed through the first books. I could never warm to Elizabeth for some reason, but her death shocked me completely. I was young and had never before read a book where one of the central characters dies so suddenly.
I think my favourite pairing has to be Dwight and Caroline, because of all they go through and because I always enjoyed the forthrightness of Caroline - she had a knack of telling it like it is.
Incidently, the book fostered a love of all things Cornish in me and I ended up living there for a couple of years, about fifteen miles away from where Nampara was supposedly placed :)