I don't like the word "minging". But then, I don't like the use of the word "fit" to describe someone attractive, which is why I always make bad jokes about gymnasiums around anyone who uses it.
As for other first-year students, most likely some of them do. Given that Oxford isn't just a bunch of upper class, posh toffs from the English gentry, and that there are people from a pretty diverse range of backgrounds/countries, I wouldn't be at all surprised to hear it used
.