"Ubuntu defaults to letting you know what updates are available,
but we want to get it out of the way now.
"The first thing you want to do is go to 'System' >
'Administration' > 'Update Manager'. You will have to supply
your password again for security purposes. Once Update Manager has
been loaded, it will search for any newer versions of software
available from Ubuntu. My newly installed copy of 8.10 Intrepid
Ibex has 215 new updates to be installed.
"At this point you want to click "Install Updates" to get your
system up to date. The system will download and install the new
updates without any user intervention. Unless you are updating a
"core" component (like the Linux kernel), you may not even have to
reboot the system."