...I've only just started getting properly re-acquainted with the quartets via the Kodály's recordings for Naxos - because they're cheap. What are the definitive recordings I should be looking out for?
With such repertoire one cannot speak of definitive recordings. I did find the Kodaly Qt to be rather bland. My Haydn quartet collection is of Lindsays and Mosaiques, who seem to me equally good in their different ways. But others on this board will have plenty of other good suggestions, too!
My brother and I went to the same piano teacher, who gave Haydn sonatas to my brother but not to me. But the volumes were in the house and I would sight-read my way through them in my teens (actually, I think that photo shows me at 8 playing the one in C, Hob. 35).
The first Haydn piece I really went mad about (at 18) was the 'Nelson' Mass (Willcocks), though also at this time the BBC used to broadcast the earlier symphonies at lunchtime and I always found those absorbing.