Porsonally
If you don't have a very long time to spend setting up all your cameras and your NVR again then there should be no need to reset both the NVR and the 7 cameras.. Corrupt FW data with lock in your Grid isn't camera issue it is NVR issue..
backup any footage you want to keep if you know you have footage right now that is important to retain? If you are asking about exporting the data from the NVR then NO it will only import the corruption back. You want a Clean Reset of the NVR..
Format of the HDD normally not needed. But if you are already almost maxed out on the HDD space and want fresh space for your recorded footage then sure Format..
What I feel is most important.. Changing the Snapshots form full time to events is very important and overlooked.. If nothing else, I would change the snapshots from full time to Motion, Alarm. If you left it setup with full time then it will fill your HDD very fast.. With it on that would be 86,400 x 7 cameras that is 604,800 snapshots in a 24hr period. For most that is a waste of space not many even look at snapshots anyway.
Your Cameras Ip setup as static If you don't Reset them then no you will not have to setup again to static. Just have to add your cameras back using the IP they are already setup with.. Yet if you reset both NVR and Cameras then yes you will need to setup static IP for NVR and all the cameras..