To Install Ubunto 9.04 version on VirtualBox 3.0

Hardware Preparation:
-Memory: 4G for host machine and 2G for Ubuntu
-Spaces: 15G or more for Ubuntu
Installation Preperation:
-From VirtualBox, change CD/DVD-ROM to mount the CD/DVD or ISO file
-Change the Network so it can read PCnet-FAST III, Bridge Adapter, nge1 (Assume Host is Ultra machine)
Install The software:
-Use default installation
Post Configuration:
-Configure Full Screen
   (From Ubuntu Devices menu, select to "Install Guess Addition" driver) -> go to the /cdrom menu to execute the *.sh driver
-Allow to run system as root
   Execute command: sudo passwd root

Source/Kaynak : http://blogs.sun.com/davisn/entry/install_ubuntu_9_04_with