When trying to reinstall I get:
E: nvidia-current: subprocess installed post-installation script returned error exit status 2
and it shows 2 versions of current.
nvidia-current-dev (270.41.06-0ubuntu1)
nvidia-current (270.41.06-0ubuntu1)
Can you send the output from:
ls -a /var/lib/dpkg/info/*nvidia*
bally@bally-laptop:~$ ls -a /var/lib/dpkg/info/*nvidia*
/var/lib/dpkg/info/nvidia-current.conffiles
/var/lib/dpkg/info/nvidia-current.list
/var/lib/dpkg/info/nvidia-current.md5sums
/var/lib/dpkg/info/nvidia-current.postinst
/var/lib/dpkg/info/nvidia-current.postrm
/var/lib/dpkg/info/nvidia-current.preinst
/var/lib/dpkg/info/nvidia-current.prerm
/var/lib/dpkg/info/nvidia-current.shlibs
/var/lib/dpkg/info/nvidia-settings.list
/var/lib/dpkg/info/nvidia-settings.md5sums
First see here to try get an idea of what I’m about to say:
http://www.pixelshine.net/howto/2011/02/21/fixing-subprocess-installed-post-installation-script-returned-error-exit-status-2/
So…
sudo gedit /var/lib/dpkg/info/nvidia-current.postinst
Remove the line:-
set -e
Save and exit gedit.
back in the terminal:
sudo gedit /var/lib/dpkg/info/nvidia-current.postrm
Remove the line:-
set -e
Save and exit gedit.
Now in a terminal run:
sudo apt-get --purge remove nvidia-current
then
sudo apt-get install dkms
then
sudo apt-get install nvidia-current
If all goes well, cross your fingers, and reboot.
Seems to be doing well… just about to restart.
And…
It’s just made things worse. 
I can’t fullscreen Chrome, every application is running slower. 
I kept on getting errors when I ran the 3rd command, and at one point it said something like “Error code (1)” or something like that.
This is a kinda hard one for me to help with … not having a PC with an nvidia GFX card.
I can’t try it in a VM as it will obviously allow me to uninstall the nvidia drivers … they are not being used … where it might not for you.
Try seeing if those set -e entries are back, if so remove them again.
then reboot to a root shell and run:
sudo apt-get remove --purge nvidia-current
then
sudo apt-get install nvidia-current
and the actual errors will help 
I got a lot of errors in the root console, so I took a video to show the output… currently uploading it to youtube so I’ll post it once it’s uploaded.
Here’s the video… Hope it gives some sort of solution to what we can do.
Try this from the root terminal:
apt-get remove nvidia-settings
apt get install nvidia-current
or the same thing from a consoe:
sudo service gdm stop
sudo apt-get remove nvidia-settings
sudo apt get install nvidia-current
Nope, no sort of effect whatsoever. Just more beautiful errors.
bally@bally-laptop:~$ sudo apt-get remove nvidia-settings
[sudo] password for bally:
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be REMOVED
nvidia-settings
0 upgraded, 0 newly installed, 1 to remove and 0 not upgraded.
1 not fully installed or removed.
After this operation, 2,163 kB disk space will be freed.
Do you want to continue [Y/n]? y
(Reading database ... 274779 files and directories currently installed.)
Removing nvidia-settings ...
Processing triggers for man-db ...
Setting up nvidia-current (270.41.06-0ubuntu1) ...
update-alternatives: error: alternative link /usr/share/man/man1/nvidia-xconfig.1.gz is already managed by x86_64-linux-gnu_gl_conf.
dpkg: error processing nvidia-current (--configure):
subprocess installed post-installation script returned error exit status 2
Errors were encountered while processing:
nvidia-current
N: Ignoring file 'google.list' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension
E: Sub-process /usr/bin/dpkg returned an error code (1)
bally@bally-laptop:~$ sudo apt-get install nvidia-current
Reading package lists... Done
Building dependency tree
Reading state information... Done
nvidia-current is already the newest version.
The following package was automatically installed and is no longer required:
screen-resolution-extra
Use 'apt-get autoremove' to remove them.
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
1 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Do you want to continue [Y/n]? y
Setting up nvidia-current (270.41.06-0ubuntu1) ...
update-alternatives: error: alternative link /usr/share/man/man1/nvidia-xconfig.1.gz is already managed by x86_64-linux-gnu_gl_conf.
dpkg: error processing nvidia-current (--configure):
subprocess installed post-installation script returned error exit status 2
Errors were encountered while processing:
nvidia-current
N: Ignoring file 'google.list' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension
E: Sub-process /usr/bin/dpkg returned an error code (1)
I’m read for tossing this laptop in the bin. XD
Bit drastic …
Gimme a while and I’ll see what I can find … or maybe you’d like to try 11.10
Ok maybe I’ll sell it for parts then. 
Naa, only kidding XD.
No worries, and I’d rather downgrade, but only if it’s a last resort. Same with upgrading.
Problem is I’ve been roped into helping with my sons maths homework … and I’ve forgot as much as I used to know.
Not to mention they’ve changed the names of everything … what was wrong with “average” ?
And WTF are mean, medain and mode ?
loooooool… how i hated maths.
Mean = To find the mean, you need to add up all the data, and then divide this total by the number of values in the data.
Median = To find the median, you need to put the values in order, then find the middle value. If there are two values in the middle then you find the mean of the two values.
Mode = The mode is the value which appears the most often in the data. It is possible to have more than one mode if there is more than one value which appears the most.
Your son’s homework is far more important than my pesky video driver problem, so don’t worry about how long you take to reply lol.
OK, after watching your wobbly video
From a console:
sudo service gdm stop
sudo apt-get remove --purge nvidia-settings nvidia-current
now rename the /usr/lib32/vdpau directory
sudo mv -v /usr/lib32/vdpau /usr/lib32/vdpau-old
now rename the /etc/OpenCL directory:
sudo mv -v /etc/OpenCL /etc/OpenCL-old
Now run:
sudo apt-get install nvidia-current nvidia-settings
Still getting errors.
Processing triggers for man-db ...
Setting up nvidia-current (270.41.06-0ubuntu1) ...
update-alternatives: error: alternative link /usr/share/man/man1/nvidia-xconfig.1.gz is already managed by x86_64-linux-gnu_gl_conf.
dpkg: error processing nvidia-current (--configure):
subprocess installed post-installation script returned error exit status 2
Setting up nvidia-settings (270.29-0ubuntu1) ...
Errors were encountered while processing:
nvidia-current
E: Sub-process /usr/bin/dpkg returned an error code (1)
OK, try this:
sudo update-alternatives --remove-all x86_64-linux-gnu_gl_conf
Then:
sudo service gdm stop
sudo apt-get remove --purge nvidia-settings nvidia-current
sudo apt-get install nvidia-current nvidia-settings