How to install Backtrack (dual boot)

First of you have to download the latest version from the official website: http://www.backtrack-linux.org/downloads/. There you have a lot of options:

-Select Backtrack 5 r3.
-Select the desktop environment of your choice (GNOME or KDE)
-Select your architecture "32" bit or "64" bit.
-Select "ISO" if you want to burn it into a dvd and use it as a live OS or burn install it in your hard drive, VMware if you want to use it in a virtual environment.
-Select the your download type, whether "direct" or "torrent".
Once the download finishes, burn the ISO file in a DVD, then reboot, & proceed as follows follow :
When you boot the Dvd, press "inter" and you'll have the following screen displayed, choose the default boot option 'number 1' & press "enter" again

Then, type startx to launch the graphical interface:

After that, you'll be logged in to the Desktop: click the installer icon and follow the instructions of this video, (please select the HD playing option in youtube for a better display).

When you finish click "restart now" and enjoy Backtrack !

You have to bear in mind that the default username in Backtrack is "root" & the default password is "toor", then in order to start the graphic interface you have to type "startx"