There are lots of retropie image's that are pretty much plug and play. You could also use a base image to build on for custom image. I scripted the robospin theme for attract-mode that comes on a lot of the popular pi images. Also, i highly recommend batocera for older pc's that will be more powerful than the pi. It will run gamecube, dreamcast, naomi games easily with something like an I3 or core dual 3 ghz.