When I run "sudo zypper packages --orphaned I see this output openSUSE-dvd-release Is it normal ? because this is a package which has the whole operating system. Version- Leap 42.3. This is not the case on tumbleweed.
Yes, that’s normal if you used the DVD installer.
I don’t see it here, because I have re-enabled the installer (a USB in my case) as a repo. But I set that repo as enabled but not auto-refreshed. That way, I am not prompted to plug in the USB unless it really needs to get something from that device.
As far as I know, you can safely remove that orphaned package if you want. That won’t remove anything else, though it might cause some packages to show up as “unneeded”.
Ok Thanks 
No but you can’t remove this package it will remove everything. LOL:)
Actually, no, it won’t “remove everything”.
Everything is a dependency or a recommend (perhaps indirectly). But removing a package does not automatically remove its dependencies. So it is needed to pull everything else in. But once they are pulled in, it is no longer needed.
In any case, it is a trivial and tiny package, so just keep it.