Throughout the entire series of Harry Potter we are constantly reminded that the Malfoys are a very important magical family. I don't think it is entirely due to the fact that they are pure-bloods, since so are the Weasleys, and nobody takes that into account. At some point I thought it had something to do with the fact that they were really wealthy, but I don't think that's all there is to it since Chamber of Secrets once Dumbledore returns to office he says that he "spoke to the other governors' families and they were all under the impression that you would curse their families if they refused" (to kick him out of Hogwarts), so:
Why are the Malfoys so important/feared in the magical world?