GameEx is a graphical DirectX based front-end for MAME, Zinc, Daphne, PC Games, and all command line based game emulators, along with being a good Home Theatre PC solution. The original goal was for it to be used on Windows XP Media Center and Arcade Cabinets although it will run on any version of Windows 98SE, ME, 2000, and XP. You don't need Windows Media Center to run GameEx.
GameEx requires the .net Framework 1.1 to run. It with will work with Version 1.0 of the framework, but was written with 1.1, and has not been fully tested with version 1.0, and I have found various issues with 1.0. If you have Windows XP service Pack 1 or above then you should already have version 1.0 of .net framework installed. In the latest and future versions of Windows the .net Framework is already installed. I highly recommend using the latest non beta version of the .net framework and service pack.
You can get the .net framework here from Microsoft.
You can get Direct X 9.0C from Microsoft here:
Windows Media Player version 9 or above is also required.
GameEx does however feature an advanced install program, which detects if the above components are not installed and can automatically download them for you.
Also for your peace of mind, the actual GameEx files themselves in the install, do not change, update or add any files, libraries, or system files at all other than ones that are purely in the Program FilesGameEx folder. GameEx also does not change or add anything in the registry other than information required to uninstall the application used by the setup application (Inno). It does register a couple of custom ActiveX controls, but again these are only located in the Program FilesGameEx folder.