My only true going-with-newbies experience was during FotR. I had already seen the movie a few times, and was running out of willing Tolkien fans to go along with me, so I took two of my good friends. Neither of them had read the books or had much interest in LOTR at all, ha.
I sat, enthralled as ever in the movie, while one of them made certain Legolas-related comments the whole time and the other sipped her drink and wondered what as going on. They were good sports, and I think they enjoyed the movie, though I expected them to be as wild about it as I was.