Why can't I download YouTube videos?

I asked a question a few hours ago about how to download this vid of an old dance recital this girl put up and got like 10 answers with different software things to try, and I tried all of them and it doesn't work. I don't think all of them could be faulty. I tried other videos too and they didnt work. On... show more I asked a question a few hours ago about how to download this vid of an old dance recital this girl put up and got like 10 answers with different software things to try, and I tried all of them and it doesn't work. I don't think all of them could be faulty. I tried other videos too and they didnt work. On the YouTube Downloader it says that there is no flash video.

I don't know what that means. Please help, I'd love to get that dance vid!!!
Update: I tried Real Player but couldn't see where you download vids from YouTube on it.

Could I need to add some plug or software to my laptop?
8 answers