-AVI, MPEG, WMV, MOV,
-MP4 (Download quicker in High Quality and HD) *Recommend
-3GP (Download quicker for Phone)
-FLV (Download quicker – Rename file .FLV – Example: Namevideo.flv)
-MP3, WAV (Audio Only)

1. copy the video url (Example: http://www.youtu . . . .)
2. go to Forinside
3. paste the video url in the url box
4. select format (AVI, MPEG, MP4, 3GP, WMV, MP3, FLV, MOV, WAV)
5. Click download

* Moreover, it can convert local videos on your PC in the formats above.

Use Forinside

it is the simplest (and also the fastest) way.

Zillatube easily download videos from Youtube… to your computer, and more (e.g. it will help you convert them, or just watch them easily anytime you want).

It works very well – http://www.zillatube.com

First off, open a new tab, and write this about:cache?device=disk in the address box. And enter.
Find the Cache directory and copy the whole Address.
Open My computer and paste in the address on the address box.
Now it will show you the stored cache.
Before you load your video, clear history/cache for simpler detecting the file you will need.
Open your designated page and refresh the cache folder and some file will appear.
keep on refreshing as the video load and you might see a file might grow up on it’s size.
if you keep on refreshing and it’s the same file that grow’s. that is your video cache.
Now you need to wait until the video is loaded completely.
After that, the same file i mentioned, rename it on it’s end on your own choice of media player , < ".flv" for me>.
Open it, and it shall replay the video you have loaded.
Go the file away from the cache box as it will auto delete when cache box reaches it size / time limit or when you clear history (cache).

Wish this helps. I will try to make video of this for simpler to teach.

Thanks. There might be some grammar mistake, I am sorry but this is my best that i am trying to give.

I believe I gaved the best answer as this method is quicker than other. It does not require any certain programs such as “real.. watever” and you might meet with some Viruses of course.
and the “mega … sumthing” is on with the subject as the host wanted “from youtube”
I gaved, the raw method.

or you can download the youtube downloader from
http://usfiles.brothersoft.com/dvd_video/misc_multimedia/youtube_flv_downloader_install3.1.exe