There are some interviews with important people on YouTube that I want to keep for life! And of course just some videos that I want! Please let me know all of the possible ways I can extract videos off YouTube. From easiest to hardest! Thank you!

Contact the owner of the video to find out a legit way to obtain the video. If the poster is the owner they can legally give you a digital copy.

Thanks!

I use this with Firefox: https://addons.mozilla.org/firefox/addon/3006