My vote is for cultural education. 

Children will learn what kind of looks are favorable and not in society. 

I guess we all have to un-learn those prejudices to really know the truth. 

If a child sees someone with a physical deformity without no knowledge of how those people are perceived by others, he/she might be curious, but hardly become judgemental.  

I think it's both.

If you have no pre-conceived ideas about someone before you've verbally communicated with them, then I'd say that you are quite unusual. For example, I'm sure I have survived several times in my life by avoiding people I judged to be dangerous at a glance.

On the other hand, some people can judge you by cultural norms that they have established. For example, I went to a Thai language meet-up, which turned out to be mostly gay men, and two or three of them were very upset that a hetero was studying with them.  

Unfortunately there are not small part of people  which like to offend on someones physical disability and to show thier advantage.  Such kind of people have mental problems I think. It's more important what person you are not  your appearance. 

Cultural education I think, most of people can not understand that we are humans with a lot of differences because implicity we raised thinking in a role model that we need to follow, talking about physical condition or behaviors. Actually I'm studying for to be a teacher of elementary school and more or less I know how through time poeple with differences have been hurt for a lot of reasons, but all this stuff borned in society thinkings about them. We just need to understand that people can not choose howto be, for example I am gay and this wasn't in my hands when I born. 

I hope in humanity. Have a nice day :)! 

It's natural. I mean, at some point in our lives, we all have judged someone based on their looks. For example, if you saw a beggar looking fat and another one looking thin, who would you give your last penny in your wallet? n_n