randime.rb

#!/usr/bin/env ruby

# REQUIREMENTS
#   1. ruby - http://rubyinstaller.org/
#   2. vlc  - http://www.videolan.org/vlc/index.html
#
# USAGE
#   1. save this file as `randime.rb` (type: `All Files`) 
#   2. beneath `__END__` below, paste in absolute folder paths containing videos you want played
#   3. double click the `randime.rb` icon to play

require 'pathname'

module VLC
  def self.exec_path
    if Gem.win_platform?
      f = 'C:\Program Files (x86)\VideoLAN\VLC\VLC.exe'
      File.exist?(f) ? f : 'C:\Program Files\VideoLAN\VLC\VLC.exe'
    else
      "vlc"
    end.inspect
  end

  def self.build_arg_str(files)
    files.map(&:inspect).join(' ')
  end

  def self.play(files)
    vlc, args = exec_path, build_arg_str(files)
    %x[ #{vlc} #{args} ]
  end
end

class WhitelistedDir < Pathname
  VIDEO_FORMATS = %w[.mp4 .mkv .avi]

  def self.all
    @all ||= DATA.read.split("\n").map{|d|new d}
  end

  def video_files
    files.select{|f| VIDEO_FORMATS.include? File.extname(f) }
  end

  def files
    return unless exist?

    pwd = Dir.pwd

    Dir.chdir self
    files = Dir['*']

    Dir.chdir pwd

    files.map{|f| self.join(f).to_s}
  end
end

class WhitelistedVideo
  def self.all
    WhitelistedDir.all
      .map(&:video_files)
      .flatten
      .compact
  end
end

VLC.play WhitelistedVideo.all.shuffle

__END__
C:/Paths/To/Your
C:/Video/Folders/Here