All of the files that are updated by the update manager gets cached at the following location.
Simply make a tarball archive and use a USB stick to take it to another machine. You need to sudo
cd /var/cache/apt/archives sudo tar -pczf updates.tar.gz *
Extract the contents in the target machines cache directory
sudo tar -zxvf updates.tar.gz
Now, run the update manager and you see that most of the stuff that you need are already marked downloaded. Simply download the rest depending on what you need and proceed with the installation. You may have to be around to approve certain dialog pop-ups.
That’s it, you have the most secure ubuntu installation on all your machines.