Coming, unsurprisingly, from Malfoy. And immediately the school is made quite suspicious - teaches Dark Arts, nobody knows where it is, Malfoy considered sending his son there. Hermione's supposition that it has to be in the far north seems to be somewhat disproven by what we'll see later - all named students and the headmaster have Slavic names, not Scandinavian ones, and Krum at least is Bulgarian.

Still about the wizarding schools, Dumbledore claims those three are the "largest wizarding schools in Europe" - or at least, were back in the Middle Ages. Likely that just means they are now among the oldest and most prestigious schools in Europe, not necessarily the largest, and certainly not the only ones. Although it does seem there isn't generally more than one school per country or per few countries. Durmstrang is apparently an international school, more than the others - I don't remember if we see the Durmstrang guests speaking any foreign language further on, but I don't imagine Draco Malfoy has all that much foreign language knowledge.

Bill interrupting Percy when for once in his life the guy is about to say something interesting: I'm curious what it is that said law did say about vampires. Perhaps just that they mustn't be exterminated or indeed killed without reason, in which case you have to wonder why that would be only in the twelfth paragraph. If I recall correctly, the only mention of a vampire later on in the series depicts them as really quite harmless and definitely not in need of extermination of any kind. More building up of the non-human races theme.

A Sorting ceremony that gives some limited data about the student numbers. Vague enough that it isn't enormously helpful, but our general idea of roughly 10 per house per year seems to fit the description.