Hi,
The answer is actually also www.youtubex.com .
YouTubex is really good you just have to do these simple steps.
1.Browse YouTube for good videos you want to download
2.Copy and Paste the URL of the Video into the form
3.Click the DOWNLOAD button to save the video
4.If there is a problem, rename the file to .flv
You will need the FLV Player to watch these videos
It can be downloaded at http://www.martijndevisser.com/blog/article/flv-player-updated
And you can also convert it into other formats like DVD, etc.
Download link : http://www.rivavx.com/index.php?encoder&L=3
See it is really simple.
Thanks for reading my long post... if you dint mind the instructions.
Have a nice day!
PS: The http://www.keepvid.com is also not a bad site. but I would recommend YouTubeX as it is simple and useful.