Aside from Ockas helpful post abvoe:
The ACPI error you reference is a harmless one, generally. It is straight from the Motherboard (Is O.S. independent) and very unlikely to cause a no-boot issue.
Booting to a black screen with blinking cursor is likely to be caused by a Display manager failure. In order to fix this, we need to know if you are using Zorin OS Core or Zorin OS Lite.
You must first enter recovery mode:
Drop to Prompt (Last item on the menu list)...
Core uses gdm, so the command to run would be
sudo dpkg-reconfigure gdm3
Zorin OS Lite uses LightDM:
sudo dpkg-reconfigure lightdm