A few guides that might be useful.
I also have several videos including how to make a gold system image using ghost.
For the vidoe on the how to make a gold image and how to then capture that see the following. It is a little long but I tried to shorten it so it is all useable no dead time.
https://youtu.be/3x0pHJyn2NA
For the full play list of videos see I think there is lots of good info for variouse topics.
https://www.youtube.com/playlist?list=PLzKI8Y3zwNuCiGZ3QHrgih8n9R1L3Ef3s
Specificly for your questions.
1 You absolutly need to install your volume licence copy on your golden system that you will be building the image off of. It isn't the license number that is the issue it is that OEM copies are not leagal to deploy out and MS does not support running sysprep on an OEM copy. There is lots of internet arguing about this point but there is my take on it. Wipe the drive and load your volume OS from the ISO don't use andy OEM installs.
see https://www.symantec.com/docs/TECH249488 step 1 is to load a clean os
2. I would recomend not joing your domain at any point with your golden image, if you did sysprep will disjoin once it is run so it might not matter but I have seen odd behavior some times while joined to a domain. Mostly because of GPO's that are applied as a result.