Among the things you guys listed, I think they would be blown away by the country's widespread tolerance and acceptance of homosexuality and gay marriage.
The word "homosexuality" wasn't even formally printed until 1869 so I don't think people back then saw it as a sexual orientation, good or bad, just a perversion known as a "crime against nature." They would probably be shocked by the amount of openly gay people and the amount of politicians who openly support gay rights. I think it would be very tough for them to see gays as a legitimate minority that deserves any kind of political representation.
If they were told that 5% of the population was gay, they'd wonder why the other 95% were so sad.
