Hello Riverman, and welcome to Seven Forums.
A system image will include everything on the selected HDDs at the time it was created including any Windows Updates that were already installed.
However, you will not be able to restore just Windows Updates from a system image backup. When you do a system image recovery
it will restore everything as it was at the time the system image was created. You could manually extract files and folders from a system image
The only way to backup only Windows Updates is to download the MSU standalone installer
for each specific Windows Update that you wanted to backup and keep it saved on another drive or partition. This will allow you to run the MSU to install the Windows Update.
Hope this helps,