I've been searching online and reading tutorials and etc about how to make my ubuntu VM dual screen(x86_64). I have first tried to run these commands:

sudo aticonfig --initial -f

which gave me the ouput of:

sudo: aitconfig: command not found

I then googled the output and followed these instructions that I tells me to install my ATI drivers onto my ubuntu.

wget http://www2.ati.com/drivers/linux/ati-driver-installer-11-5-x86.x86_64.run
sudo sh ati-driver-installer-11-5-x86.x86_64.run --buildpkg Ubuntu/natty
sudo dpkg -i *.deb
sudo apt-get -f install
sudo aticonfig -f --initial --adapter=all
sudo reboot

It all works well until I input sudo apt-get -f install which gives me the following output:

sudo apt-get -f install
Reading package lists... Done
Building dependency tree       
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 25 not upgraded.
3 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Setting up fglrx (2:8.850-0ubuntu1) ...
update-alternatives: error: alternative link /usr/bin/aticonfig is already managed     by x86_64-linux-gnu_gl_conf.
dpkg: error processing fglrx (--configure):
subprocess installed post-installation script returned error exit status 2
dpkg: dependency problems prevent configuration of fglrx-amdcccle:
fglrx-amdcccle depends on fglrx; however:
Package fglrx is not configured yet.
dpkg: error processing fglrx-amdcccle (--configure):
dependency problems - leaving unconfigured
dpkg: dependency problems prevent configuration of fglrx-dev:
fglrx-dev depends on fglrx; however:
Package fglrx is not configured yet.
dpkg: error processing fglrx-dev (--configure):
dependency problems - leaving unconfigured
No apport report written because the error message indicates its a followup error     from a previous failure.
No apport report written because the error message indicates its a followup error     from a previous failure.
Errors were encountered while processing:
fglrx
fglrx-amdcccle
fglrx-dev
E: Sub-process /usr/bin/dpkg returned an error code (1)

At this point, I don't know what to do since running:

gksudo amdcccle

For the record, I have 3D acceleration turned on. The following is my GPU for my VM

lspci | grep VGA
00:02.0 VGA compatible controller: InnoTek Systemberatung GmbH VirtualBox Graphics     Adapter

Any Help on how I can make my VM dual screen with Ubuntu would be great. Thank you in advance.