Winston Smith is an intelligent, political dissident, who vehemently opposes the Party and is not brainwashed into believing the government's overt lies. Winston actively seeks evidence to prove that life was better before the Party usurped power and is a thoughtcriminal, who writes "DOWN WITH BIG BROTHER" numerous times in his secret journal. Unlike the Parsons and the overwhelming majority of the population, Winston Smith is an independent thinker and one of the last remaining genuine human beings not obsessed with Big Brother.
In contrast, the Parsons are depicted as ignorant, completely orthodox Party members, who accept and believe the government's propaganda. Mr. Parsons is a staunch supporter of Big Brother and sacrifices his personal time to prepare for the Hate Week festivities. Their children are depicted as aggressive supporters of the Party, who are trained to spy on thoughtcriminals and report them to the Thought Police. Winston fears the children and discovers that they even turned in their father for engaging in thoughtcrime.
The biggest difference between the Parsons and Winston Smith is the passing of children. Winston does seem to be older than the Parsons and is still able to think for himself. The Parsons however, have bought into the society and the worship of Big Brother enough to be completely brainwashed. Here is how the narration describes Parson:
He was a fattish but active man of paralyzing stupidity, a mass of imbecile enthusiasms - one of those completely unquestioning, devoted drudges on whom, more even than on the Thought Police, the stability of the Party depended.
Every character trait within this quote from the second chapter is the complete opposite of the questioning and intelligent Winston.
The Parsons' children were consumed with acting like the Thought Police and getting to see the hanging. This demonstrates what the power of a generation can do with education. Winston could still remember glimpses of life before the Party, these children were consumed with the tenants on which the Party stood.