EmuNations

Launchbox is a front-end wrapper for emulators. Not only does it automatically download box art for games, it also grabs fanart, screenshots, logos and more to create an immersive experience via BigBox.

It also supports arranging and filtering by genre, platform, ESRB rating, developer, publisher, genre, etc. It also includes automated import processes for your MS-DOS games, ROM files, and Steam in order to help get you up and running as quickly as possible. Game box-art and metadata can also be automatically downloaded from their Games Database or community-based online databases.

Playnite is an open source video game library manager with support for 3rd party libraries like Steam, GOG, Origin, Battle.net and Uplay. While providing one unified interface for your games, it includes game emulation support, fullscreen mode, themes and much more.

Requires Windows 7+ and .NET Framework 4.6 

Modern fork of x360ce built with SDL3, ViGEmBus, vJoy, Windows MIDI Services, HelixToolkit, .NET 10 WPF, and Fluent Design. Turn any input device into any virtual controller:
Gamepads, joysticks, keyboards, mice, and touchscreens — mapped to Xbox 360, DualShock 4, DirectInput, MIDI, or Keyboard+Mouse output that games treat as real hardware.

Batocera.linux is an open-source and completely free retro-gaming distribution that can be copied to a USB stick or an SD card with the aim of turning any computer/nano computer into a gaming console during a game or permanently. Batocera.linux does not require any modifications and can run on Windows, Macs, Raspberry Pi and even some handhelds.

AntiMicroX is a graphical program used to map gamepad keys to keyboard, mouse, scripts and macros. You can use this program to control any desktop application with a gamepad on Linux and Windows. It can be also used for generating SDL2 configuration (useful for mapping atypical gamepads to generic ones like xbox360).

RomVault is a GUI-based rom management tool and can be seen as an alternative to Clrmame Pro with additional features at managing large numbers of DAT and/or Roms in a more streamlined process. 

DXGL is a ddraw.dll library replacement for Windows running on OpenGL. It is designed to overcome driver issues, particularly in Windows Vista and newer operating systems while also adding various enhancements to the graphics output such as display scaling and filtering options. DXGL supports the DirectX 7.0 graphics APIs, however it is currently under development and does not work with many programs.

It's currently in an alpha stage, but several applications and games already work.

DOSBox-X is a free and cross-platform DOS emulator for running DOS games and programs. Started as a fork of the DOSBox project, it retains compatibility with the wide base of DOS games and DOS gaming DOSBox was designed for. But it's also a platform for running DOS applications, including emulating the environments to run Windows 3.x, 9x and ME and software written for those versions of Windows. DOSBox-X aims to be a complete DOS emulation package that is both fully-featured and easy to use, covering all pre-2000 DOS and Windows 9x based system scenarios. 

While they have made efforts to maintain and improve the emulation accuracy of the hardware and many more ways to configure the DOS virtual machine, they also try to strike a balance between emulation quality, speed, and usability, including improving the out-of-the-box experience for new users who want to run DOS programs or games, as well as implementing emulation that is accurate enough to make retro-programming possible with confidence the program will run properly on actual hardware.