Referring to a gay person as defective, and assimilating him/her to a pedophile is incredibly offensive.
But lets extrapolate your pedophile analogy a bit. I'd be more comfortable if we compare both gay and straight people to pedophiles. Like gay and straight people, a pedophile is wired the way he or she is wired - they are attracted to children. The benefit that gay and straight people have is that we can find other gay and straight individuals like ourselves who can consent to a relationship. Pedophiles are predatory, and society needs to be protected against the damage that their wiring can cause. In none of these cases - gay, straight, or pedophile - has the person chosen to be the way they are.