What's the least organ damaging/most body friendly of the otc painkillers? tylenol, (acetaminophen) advil, or aleve? (i realize those are brand names...)

All are safe: None will injure you used as directed. Some folks get elevated liver function tests from even a little Tylenol (acetaminophen). Advil reversibly damages the kidneys if you get dehydrated on the stuff. Same for Aleve. Some folks get liver sensitivity to any of these. I would choose the one that gives you the best pain relief, drink plenty of water, and not worry about this.