Well, Holy Basil is a good one to start with! But also some other good ones are basil, chamomile, calendula, Comfrey, mint, Echinacea, Lavender, lemon balm, rosemary, sage, and yarrow.

All that said though it really depends on what your goals are, where you're growing and why you're growing something. I have probably about a hundred different herbs I will be growing, but my goals are a working apothecary and selling quality herbs. Also you want to look at what health conditions you/ your family have and what prescriptions you maybe taking when considering any herbs.