Install and Config Virtualbox_2.4.x on Ubuntu 9.04 host (part 1)

Overview

I have just installed Ubuntu 9.04 and used as the primary OS. Ubuntu have been enormously developed in recently time with the support of developers. Ubuntu was integrated almost features which Window OS had, but there are some tasks the users need to use window such as control a scanner. I hope this features will be added on Ubuntu so far, however this disadvantage can be temporary tackled by using the above solution. Firstly, the users can install Virtualbox as an Virtual Machine on Ubuntu host. Secondly, create a new virtual machine in Virtualbox and install Window OS to use in some cases. Furthermore, the users can configure some add-on to use sharing Data between Linux host and window client. Here are some instructions in detail.
I. Download and install Virtual box
You need to download this software from website Virtualbox, then install it. However, i recommend that you do not do this manner because it is not convenient. I suggest that you should do as following steps:
1. Adding an CA into your "Software source" (Repository) by using terminal command (root mode)

wget -q http://download.virtualbox.org/virtualbox/debian/sun_vbox.asc -O- | sudo apt-key add -

2. from "System->Administration->Software Sources", selecting tab named "Third Party Software" , and click add button to type this text:
deb http://download.virtualbox.org/virtualbox/debian intrepid non-free
3. Reinstall or install
- for reinstall:
sudo apt-get remove virtualbox-ose virtualbox
- for new install:
sudo apt-get install virtualbox
or type this command:
sudo aptitude install virtualbox
4. Find your icon in Applications->System Tools->Sun VMx VirtualBox
or Accessory - > sun virtual box.
the above image is about Virtual box after installing and creating an new VM XP OS