Installation Of a Virtual OS With The Help Of Virtual Box OSE

If you into testing programs and frustrated with the system behavior while doing this, you have landed the correct place.
Open source software VirtualBox OSE offers a great solution for this.
The reason why you would ever like to use a Virtual OS may be because of the following reasons..
 You may be into system testing and you would like to test programs on a real time system.But you have a fear that it may crash your system to irreparable damage. Using VirtualBox OSE, you can install a Virtual OS on a Host OS. Remember that any modifications, damages to the Guest OS does not in any way affect the working of Host OS. In fact, that's the best part of it!
Using Virtual Box , you can use as many as 10 operating systems one one host.
VirtualBox OSE 

To avoid confusions further, here are some terms that you must have grasp on..
Host OS- It is the base operating system. This OS will serve as the Host for other Guest OS. The Guest OS will use resources like hardware (most importantly RAM and hard-disk) from this OS. There can be only one Host OS.

Guest OS- As the name suggests, this OS is like Parasite which will thrive on the resources provided by the Host OS. You can have as many as 10 OS's on a typical VirtualBox. This number normally depends on the richness of your RAM.

When you use the Guest OS, you have the impression that you are using a real OS installed on real set of hardware.
here is a step by step guide for the installation of Virtual OS using VirtualBox OSE.

 1.Start VirtualBox OSE, the following screen appears. Here select New on the leftmost side of window.

 2.After this the following window appears. Click on next. the name of the new Virtual Guest. This can be anything that you wish. Also, the window asks you to select the name of the OS and the version you want to install from a drop down menu. If the OS that you wish to install does not appear in the list, you can always select "Other" option in the drop down menu.
Here I have selected Linux operating system and am installing Ubuntu version. Click next.

 4.The net window asks you to select the RAM that you wish to use for your Guest OS. After selecting suitable RAM as per the need of the OS you want to install, click next.

 5. Now you have to select the size of the hard disk. This is the most crucial stage. The window asks you to select the type of hard disk.
Dynamically expanding storage.
Fixed sized storage.
To be safe in future select the first option, ie.  Dynamically expanding storage. Having done this, you have a dynamic hard disk which will expand as you go on storing data in the Guest OS.  The hard disk will have a extension of .vdi. It stands for virtual disk image.

 6.Select the size of the hard disk. Of course, the hard disk space is utilized from the Host OS. Click next.

 7. Th next two windows will confirm your action of the OS you want to install. They will show the configuaration of the RAM and the hard disk you have selected. Click Finish.

 8.Select the type of bootable media from the list. Most systems dont support floppy drives these days, so you have no option but to select CD Drive. Click next.

 9.Insert the CD for the OS that you have selected. and Start the new OS.

10. Install the OS as you normally do. And complete the installation.
   Done that's it!!

The following images show A guest OS- Windows XP installed on Host OS- LInux Mint 9.

The Mouse issue...
While in the Guest OS, the mouse usage will be restricted to the Guest OS only. To switch back the mouse to Host OS press Right Ctrl key (by default, you an always change this setting.)