Some of this is fair to handle yourself. Tightening loose hardware, lubricating hinges and rollers with the right garage-door-rated lubricant, and clearing track debris are all reasonable weekend jobs, and they extend the life of hardware that's already decades old.
What isn't worth doing yourself: anything involving the torsion spring. A spring under tension on a door this age has had 35-plus years to corrode or fatigue unevenly, and the failure mode when one lets go isn't gradual - it's sudden and it can break fingers or worse. Same goes for cable replacement; a frayed cable under load behaves unpredictably.
If your opener dates back close to the house itself, don't try to diagnose a circuit board issue on your own. Original units from that era don't always have documentation easily available, and guessing at a fix can mask a bigger problem, like a drive gear that's about to fail entirely.