Re: Older D&D systems questions.
OD&D actually does not actually have class as race, that started with B/X, I think, in 1981. If you think of OD&D as the sort of prototype of all the systems that followed you will not go far wrong.
It is a joyful thing indeed to hold intimate converse with a man after one’s own heart, chatting without reserve about things of interest or the fleeting topics of the world; but such, alas, are few and far between.
– Yoshida Kenko (1283-1350), Tsurezure-Gusa (1340)