I'm amazed noone here has mentioned RetroPie[1]. A model B Raspberry Pi or even a Zero (if you can get one) should play NES games perfectly fine. You can get USB NES controller adapters pretty cheap or some knock-off USB NES controllers instead. I have a SNES-USB adapter for my setup that takes two SNES controllers. [1] - https://retropie.org.uk/
I'd personally recommend Lakka[1] (Kodi's distro modded to boot straight to Retroarch) over it, having used both. Worth it for fewer problems with controller mappings, if nothing else. Boots to a usable GUI in ~3-4s on a Pi2, which is nice. If you're using a Pi it's easy to try both before deciding, so may as well check it out. Anyone in the market for hardware, I've found that the abilities of various devices tend t…
A little pedantic, but Lakka is based on OpenELEC (and may have switched to LibreELEC by now). OpenELEC/LibreELEC are buildroot based OSs that boot straight into Kodi. Neither are affiliated with the Kodi project - but the devs get along and communicate.