Basically, the DHCP service service would not start after they experienced a power outage. After a quick investigation I quickly discovered the DHCP database was corrupted. I found this out via the Event Logs > System.
The DHCP database is located here:
I just went in (after making sure all client computers were off) deleted the database; restarted the service and re-built the IP allocation tables... Fixed.
Note: Make sure that if you enabled another DHCP server in the meantime, to disable it or this Window DHCP server will not start due to "seeing" another DHCP server running.