I was all ready to say no that there wasn't anyone I was embarrassed to have read until I read the first comment about Barbara Cartland. My sister brought a few of them home after spending a college semester in England in the 70's and I got hooked on romance when I was about 13. After collecting about 50 or so I moved on to other writers, probably Harlequin books. My parents always encouraged us kids to read so the first adult book I read was Dr No by Ian Fleming when I was 12 or so.
If my sister is near I will ask her what something means if not I move on. If I think about it later I will ask her or look it up or sometimes type the word into Word and look at synonyms. I was also a cereal box reader as a kid and I remember reading Dr No when I was about 11. Not appropriate, maybe, but my parents always encouraged us kids to read and I still have wonderful memories of reading Golden Books with my Mom and Dad at bedtime.