Certainly. You seem a bit mixed up with the timeline. The Gaunt scene must have been, hm, in the twenties or thirties - the Brideshead Revisited era, say. Within a year or two, Merope gives birth to Voldemort, who enters the orphanage not long after when she dies. He goes to Hogwarts roughly at the time of WW2, and then a few years after the war, he kills his father and his grandparents, disappears for a few decades and then returns for his big reign of terror.

While we're on the topic, though, the thing with Lavender Brown really doesn't make boys, and Ron in particular, look good. He is interested in her for apparently no better reason than that she shows interest in him. Then again, in his defense, it's the first time a girl really does that, and his self-esteem in such matters has never been too high, as we see in his exaggerated reactions to Ginny's love-life.