I've had to reinstall 10.6.8 twice. The first time I went through the 8 or 9 updates individually - downloading, installing, restarting - for what seemed an eternity. The second time I used the Combo Update and it was "no fuss, no muss, no bother".
I had to do a couple of minor things like upgrade my Safari to 5.1.7 ( and maybe that's now taken care of) but it was much easier and faster. The other downside of doing all the updates separately is that it's 8 or 9 opportunities to make a mistake.
iMac (Retina 5K, 27", 2017), 3.4 GHz Intel Core i5, 8GB RAM, 2400 MHz DDR4
OS High Sierra 10.13.6
Canon MX710 Printer
Epson Perfection V500 Photo Scanner
Time Machine on 320GB OWC Mercury OTG Pro
Carbon Copy Clone on 500GB OWC Mercury OTG Pro