How to install virtualbox and 'OS' in Backtrack R2

The first, download and install the program VirtualBox. The use of virtual learning box pentest using BackTrack 5 would greatly help us to train our skills-skills before pentest pentest world of reality. Therefore, we must first install Virtual box on our BackTrack. But now the problem if we use the direct download with apt-get install virtualbox-4.0 then during execution vbox will be erorr. So go through the following steps that I will mention.
The reason why there is erorr during execution Vbox is because the kernel headers installed on BackTrack 5 has therefore we must install it first. Type the following code in the terminal

• root@bt:~# prepare-kernel-sources
• root@bt:~# cd /usr/src/linux
• root@bt:/usr/src/linux# cp -rf include/generated/* include/linux/ 

Then edit the sources.list file and add the repository Vbox by typing the following command:

• root@bt:/usr/src/linux# echo deb http://download.virtualbox.org/virtualbox/debian lucid contrib

Then download virtualbox package by typing the following command:

• root@bt:/usr/src/linux# wget -q http://download.virtualbox.org/virtualbox/debian/oracle_vbox.asc -O- | sudo apt-key add -

 Then do the update by typing the following command:

• root@bt:/usr/src/linux# apt-get update

• root@bt:/usr/src/linux# apt-cache search virtualbox 

 Then do a virtual box installation by typing the following command:

• root@bt:/usr/src/linux# apt-get install virtualbox-4.2

 

Congratulations Now virtual box installed ..

 Second, install the operating system already installed on virtualbox on Backtrack. In this example I take the operating system Windows XP SP3, Here's how to set it up :
  
Open the virtual box  :

 

Specify the name of the system to be installed, and click "next"

At this stage we need to determine value of memory RAM to use at system and click "next"

 At this stage choose as default is"Create New Hardisk"

Choose "VDI" to determine type of Hardisk on Virtualbox

Choose as default is "Dynamically Allocated"

Determine size of hardisk virtual, the amount depends on the system capacity will be installed

 This is final step to prepare vitual disk to install other system in this case I install Windows XP SP3, This screenshoot when i try to install Windows in vBox :

 Press F8 when this dialog appear

 Congrats, In this screen we have Instaled Windows XP SP3 in VirtualBox

After a successful windows operating system we install, configure the network so that the machine is installed virtualbox windows can ping Our Laptop(My OS is Ubuntu)like this Picture 

Now We can connect from Machine virtualbox to Our Laptop...