Raspberry Pi 3 + OpenELEC = problem solved!
Tell me more, I've played around with Arduino a little in the past but never a Raspberry Pi
There isn't that much to it really. OpenELEC is a Linux distro that uses Kodi for media play back. The Pi has hardware decoding for codecs like H264 so makes for a very popular media player. Needs a few accessories (PSU, SD card, HDMI cable, case, remote etc) to make it all work but should be achievable for around $100. OpenELEC is very easy to install and unless someone had told you you wouldn't know it was Linux i.e. no need to use the command line.