Ok heres something i learned today. if you want to dowload a video from you tube then here a quick way without a third party software.
lets say the address (url) is
outube......blah blah blah wil become 3
outube.com blah blah...
then you highlight and delete the fist part of the address up to the O in you tube as above then add 3 to the front and press enter this will give you a page to select the file type you want,
note you cant always get a mp4 file and may have to have a flv file which will play with Vlc media player