My father got me into playing on his C64 before I could actually read. :-)
I think one of the first games I played by myself was
Stix.
And then many other games followed.
From the top of my head I remember Ghostbusters, Pegasis, Giana Sisters, Bubble Bobble, Hanse, Heart of Africa, Summer/Winter Games, H.E.R.O, River Raid, Boulder Dash, Paper Boy, Gumshoe, Kane, Donkey Kong, Popeye, Aztec Challenge, and Fort Apocalypse, but I know there were many more.
*nostalgia*
I still remember how my father taught it to me
L shift-O shift-2 shift-4 shift-2 , 8 return