I too, think you are behaving a little OTT using the same examples as buildersmate
your son, unfortunately, is going to come up against many more comments about his abilities, both negative and positive. Calling him a freak, which may have a misheard comment because yr son is bound to have been sensitive after being asked to read in class, is definitely not teacher like behaviour, obviously and he should indeed receive an apology if the teacher did say that. I suspect it will be his word against hers
I also suggest you await the outcome of the investigation and then decide what is best for your son, not what you feel is best to achieve what you feel you want - and that is the teachers job, that is unlikely to happen