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.