I had to read C.S. Lewis, because. I read most of the 'classics' but then they accidentally introduced me to Heinlein and Harlan Ellison (yay libraries with reading rooms). Big mistake to throw that kind of bait to a budding nerdling. I think the series I first fell for, the one that made me realize that words on dead trees can be more than the sum of their parts, was E. E. Smith's Lensman books. They are in that 20's-30's EVERYTHING! EXCITING! style, but the stories and settings all hold up nearly a century later. I inhaled everything science fiction I could get my hands on.
Yes!. I mentioned my dad had a small collection of books - the only ones he let me read were his E.E "Doc" Smith books. I think the rest were too adult for me at the age of 10/11. I devoured them and I'm sure that's where my love of science fiction started. There was a great comment on Hacker News in the discussion yesterday about Towel Day. The golden age of Fiction is 12.