I get what your saying, but I think another thing that was probably more easily seen in the books is blood and heritage. There was all the pureblood mania in the books, where they thought they were better than everyone else due to their background and their bloodline. Then we have the half-bloods, who were seen as somewhat common ground--they weren't the best of the best, but they weren't at the very bottom either and they were usually accepted by everyone. Then there are the muggleborns who were sometimes treated like dirt. That bit reminds me of the caste system in India...where you are born is where you stay, and you can't move in and out of ranks (either that or it is very VERY uncommon). People judged you based on the blood in your veins, which I think was a bit more common in the Harry Potter books rather than the muggles vs. wizards bit

It's hard to say whether or not the bit about magic creatures being discriminated against was accurate because there is no real life proof to go off of there, but I assume that is how the caste system in the Wizarind World would go. Even werewolves were looked at differently because of a disease they were inflicted with, like lepers.