There is always VLC, all purpose media player: http://www.videolan.org/vlc/download-windows.html

And Firefox, plus I suppose Google Chrome, or any Mozilla based engine would run Addons: DownloadHelper, or Download Flash and Video, for Flash Video Downloads.

*Be aware there are Copyright issues Downloading some material. Check into that before downloading.

Installing Audacity ( http://audacity.sourceforge.net/download/windows ) you can Import a Video and Export it’s Audio, in many Formats depending on which Codecs are installed. Also Import Audio, and export in another format, plus record, multitrack, edit.

Have fun,

Best regards,

Abraxas.