1. No you can not use Launchbox/Bigbox as a server like plex it must be installed on your system, or at worst on a network drive, but that likely wont work to well running the actual program from.
2. Bigbox is paid software, so it will never be distributed like that, and if we see that it is we will block the License. Also distributing bios files is also highly illegal, just as bad as roms. Also most open source emulators have terms and conditions to there open source licence, and one of those is they can not be distributed with paid software.
So in the end, no it cant be used as a server, and no it can not be distributed in the way you are asking.