You cannot disable Win10 Updates, only delay them, and for not very long at that...
Which mod are you wondering about the eye-candy with?
Steam and SH4 do nothing to interfere with normal computer operations. Once you install Steam, you will have a log-in pop-up every time you boot the computer, but that can be disabled in the Steam settings easily enough. One important thing to watch for when installing an older game such as SH4 and Steam, is that Steam will default to installing in "C:\Program Files (x86)" (as documented throughout this portion of the SubSim web site), and as such, the games' "Library" (the Steam term) will be below that, also in the Program Files folder, which presents problems when you attempt to apply mods to the game. If and when you do purchase (whether Steam or another vendor), be sure to install into a folder of your own creation that is outside of any of the Windows "protected" folders, such as the "Program Files" folders, but also any others under the UAC (User Access Control) of Windows.
