Yes, you can, both legally and practically, however it can be more difficult to gain an exemption to homeschool a special needs child. Some of the greatest achievements in homeschooling have been by parents of special needs children.
Neither are 90% or other homeschooling parents. It depends on what you mean by qualified. No one is more qualified to educate your children than you their parents. The vast majority of homeschooling parents are not professional teachers.