I've not filed a tax return in years, what should I do?

Have you only earned income from a salary and had no further deductions? How long have you not been filing and what has your annual income been?

I haven't filed for about 5 years. Any money that I did make was salaried and had tax deducted.
Year 1: no income
Year 2: about R 60 000 annually.
Year 3: about R 60 000 annually.
Year 4: about R 84 000 annually.
Year 5: about R 84 000 annually.

You fall below the threshold of having to file tax returns based on the information provided so you don't need to worry about it.