A good downloader.
http://www.youtubedownloadersite.com/It requires a little setup, creating a folder to copy to (these are mp4's, etc., video plus audio files), and another folder to "Convert" to (can convert to mp3's, audio only).
If you need help getting, setting up, or using, let me know. Never had virus, malicious software, etc. problem, but I do keep my antivirus, etc. updated.
Have used this software on other websites to get video and audio files.
Happy New Year's everyone!