In the book Goblet of Fire, Hagrid claims that when he was 6 he could pick his dad up and put him in a dresser, and how tall his mom was, I have not the slightest clue. Does JK Rowling give any estimations or exact heights for Hagrid's parents?
I can give you a tiny bit more info. We know that Grawp - Hagrid's brother - is quite small:
See, with giantesses, what counts is producin' good big kids, and he's always been on a bit on the runty side fer a giant - on'y sixteen foot -'
Harry Potter and the Order of the Phoenix - p.609 - Bloomsbury - Chapter 30, Grawp
So it's not unreasonable to surmise that Fridwulfa (Hagrid's mother) may have been a relatively short giant, with the giants Hagrid saw being 20-25 feet:
'How big are they?' asked Ron in a hushed voice.
''Bout twenty feet,' said Hagrid casually. 'Some o' the bigger ones mighta bin twenty-five.'
Harry Potter and the Order of the Phoenix - p.377 - Bloomsbury - Chapter 20, Hagrid's Tale
As for Hagrid's dad, I can say in addition that when Hagrid was about seven or eight feet tall, his father was short enough to sit on his shoulder:
Hagrid got up, went over to his dresser, opened a drawer and pulled out a picture of a short wizard with Hagrid's crinkled black eyes, beaming as he sat on top of Hagrid's shoulder. Hagrid was a good seven or eight feet tall, judging by the apple tree beside him, but his face was beardless, young, round and smooth - he looked hardly older than eleven.
'Tha' was taken jus' after I got inter Hogwarts,' said Hagrid, croakily.
Harry Potter and the Goblet of Fire - p.395 - Bloomsbury - Chapter 24, Rita Skeeter's Scoop
Hagrid's mother was a giant, whose average height is considered to be ~20 feet tall according to Hermione GoF:
'Well, I thought he must be,' she said, shrugging. 'I knew he couldn't be pure giant, because they're about twenty feet tall.
We don't know anything about the father's height aside from GoF quote you mention:
Tiny little bloke, my dad was. By the time I was six I could lift him up an' put him on top o' the dresser if he annoyed me
There's really no more info, on Pottermore or any interviews.