I am running Ubuntu Server 11.04 in VirtualBox as a development server. After install, because I'm new to Ubuntu, I added the Unity desktop to help me finish configuring everything. Now, I would like the machine to default boot into the console, as it normally does for Ubuntu Server. But I would also like a GRUB entry option to boot into the GUI if I so desire. How can I accomplish this? Thank you.
You want a GRUB entry to boot into the CLI, and also a GRUB entry to boot the same partition, but start X?
Far simpler: remove your display manager (by default, I believe gdm3) or disable it. This will cause Ubuntu to boot into the CLI. Then if you need the GUI just type "startx &" at any console.