Once you installed Ubuntu, you might want to get the latest patches and updates. Using Ubuntu's easy to use package manager Aptitude, the OS along with all future packages that is installed using this manner can be kept up to date.
sudo apt-get update
sudo apt-get upgrade
y
to start the installation process.Also you could just hit enter, when presented with a choice the capitalized choice is the default, and is selected if you hit enter and type nothing.