I am very fond of Tintin. I’ve read all of the books, and own a large number of them. I’m also looking forward to the movie, and I REALLY hope they don’t mess it up.
Cthulhu I am less familiar with, other than in a general pop culture sort of way. My main exposure is through Neil Gaiman’s short story “A Study in Emerald,” which is a Cthulhu/Sherlock Holmes mash-up. (My puny human mind might not be able to handle Cthulhu without more familiar trappings. Or I’ve just never gotten around to reading the original Lovecraft stories. One of the two, for sure.)