Answered by The Reader
If you have only a limited time for reading, I’d first read (naturally) Travelers’ Tales Ireland. I’d read How the Irish Saved Civilization by Thomas Cahill. I’d read Angela’s Ashes by Frank McCourt. I’d read A Book of Migrations by Rebecca Solnit. I’d read Insight Guides Ireland.
As for safety, your biggest potential danger is in driving the country roads. They are narrow, and of course, you drive on the left, so if this is new to you, drive with care, don’t drive at night or in heavy rain storms. Other than that, observe the usual big city precautions in Dublin and Cork and Belfast and you’ll be fine. Ireland is quite a safe and friendly place.