This script is a WIP. Currently, the main functionality works as intended. Steam Big Picture launches automatically when the OS boots, then explorer starts automatically after a delay, which allows you to exit to desktop via the menu without needing to launch a shortcut for Explorer.exe first.

What remains to be fixed:

Completely suppressing the taskbar from appearing when Windows Explorer automatically launches in the background. The taskbar displays temporarily for ~1 second when explorer.exe launches, which makes it appear over the Big Picture UI; and then it disappears. This is not intended behavior, and it is visually distracting. Potential solutions are a script written with NIRCMD, or changing the z-order of explorer.exe (or Steam) temporarily via a C++ application. I'll have to do more research.

Coremeter could potentially be adapted for the z-order method

https://github.com/cppshane/CoreMeter

Disabling the Windows welcome screen entirely. Currently the Boot logo is removed as intended, and the script is set to log the user account which ran the script in automatically. The welcome screen still remains, and will be disabled in future versions of the script. Going to have to write a custom C++ application to do so since there is no off the shelf way to disable the Welcome Screen on Windows 11.
Setting Steam to start as admin (VBS script to suppress the command prompt window set as the shell at boot > VBS script launches the batch script > batch sets steam big picture as the shell > batch launches steam as admin > delayed explorer batch script resets the shell to the VBS script so Steam launches as the default shell at boot.)

GamesDows

The Enable GamesDows script makes Windows boot straight into Steam Big Picture without displaying any Explorer UI elements to ensure a Game Console like experience on Windows. I made this because I have a Steam Deck and I want the experience to mirror that of Steam OS as closely as possible. However, this will work on any Windows PC, the commands are not specific to the Steam Deck.

Here's a breakdown of what each part of the script does:

1. Set Steam Big Picture as Default Shell:

Disables echoing the command to the console (@echo off).

Enables the use of advanced scripting features (SETLOCAL EnableExtensions).

Changes the Windows shell from the default explorer.exe to Steam's Big Picture mode. It modifies the Windows Registry to make Steam.exe -bigpicture the default shell that launches upon user login.

2. Create and Set Up a Delayed Start Script for Explorer:

Defines paths for the Steam folder and Delayed Explorer Start script name.

Creates a batch file (DelayedExplorerStart.bat) that checks if the user is logged on. If the user is logged on, it sets the shell back to Windows Explorer (explorer.exe) after a delay, allowing Steam Big Picture to launch first.

After booting directly into Steam Big Picture, explorer.exe is launched automatically so that the "Exit to Desktop" menu item in Steam Big Picture works as expected. You do not need to launch a shortcut from within Big Picture first in order to be able exit to the desktop. The menu item will work as intended after the GamesDows script is run, no additional work necessary.

3. Create a VBScript to Run the Batch File Silently:

A VBScript (RunBatchSilently.vbs) is created to run the DelayedExplorerStart.bat to suppress the command prompt window/run silently. This means the batch file will launch explorer in the background without opening a visible command prompt window over the Steam Big Picture UI.

4. Set Up a Scheduled Task to Run the DelayedExplorerStart.bat Script at Logon/bootup:

Creates an XML file to define a scheduled task. This task will trigger the VBScript at user logon.

Deletes any existing scheduled task with the same name and creates a new one using the XML configuration. This ensures that the DelayedExplorerStart.bat script runs every time the user logs on.

5. Enable Automatic Logon and Disable Boot UI:

Configures Windows to automatically log in with the current user account (AutoAdminLogon).

Sets an empty default password for automatic logon (DefaultPassword). If you have a password, please insert it into the empty quotation marks in the batch script inside this command. This is the command that inputs the user password, it is set to be blank by default. I have put a placeholder in the script breakdown here for clarity:

reg add "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon" /v DefaultPassword /t REG_SZ /d "YourPasswordGoesHere" /f

The command "bcdedit.exe -set {globalsettings} bootuxdisabled on" disables the boot user interface (bootuxdisabled). This disables Windows Branded Boot, and therefore no Windows logo is displayed when the OS boots.

Disable GamesDows Script

The Revert script reverts all changes, which resets the Windows configuration to what it was before the Enable GamesDows script was run. If the script fails to revert any of the changes, they can be manually removed. If needed, delete the Scheduled Task created in Task Scheduler called "RunDelayedExplorerStart", as well as the files the Enable GamesDows script creates.