When I was about four I seem to remember us singing:

'Dan, dan the dirty old man,
washed his hair in the frying pan,
combed his hair with the leg of a chair...'

then I'm not sure - maybe it just went 'Dan dan the dirty old man' again.

And also -

Elvis Presely
Girls are sexy/God damn sexy (depending on how 4 we were!)
Sitting in the back seat
Drinking Pepsi!

And possibly one of my first tastes of swearing - that rhyme you do (like eeny meeny miny mo) for deciting who's 'it' in a game of tig - was
'Ip dip dog shit
fuckin bastard,
dirty git" - I doubt we knew what any of the words meant though!

xLx