Yes it is important to have all members of staff develop positive attitudes towards children with disabilities. But the parents  positive attitudes and positive involvement is even more important. As Daniel stated, the children belong to their parents and they decide which school, class etc that they child attends. 

While listening to the video, I remembered a child whose parents denied that the child had a disability even though they were sent to do an evaluation and it stated such. It was challenging because the staff wasn't fully trained in teaching a child with a disability. We all tried to support him, we talked to the  children about ways we can help him. We also had to educate parents who complained about his outbursts on the children. Only when the child moved on, and one off the requirement from the school was for the parent to get an aid, then the parent accepted that her child has a disability. It's sad to know that she took a long time to accept it when that time could have been used to help her child.