WSUS Offline Update which allows you to update any computer running Windows or Office, without it needing to have an internet connection.
Essentially all you need to do is run the program on a PC which can get online, and tell it exactly what you'd like to download. Options include patches for Windows XP, Server 2003, Vista, 7, Server 2008 and 2008 R2, both regular 32 and 64-bit editions, as well as Office 2007, 2007 and 2010.
WSUS Offline Update will then download the updates for your chosen product, optionally copying the files to a USB stick, or even creating a suitable ISO image, ready for burning to a CD or DVD.
On the target computer, the UpdateInstaller.exe makes it easy to choose the update options you need (including the ability to back up your existing system files). And then a click on the Start button will quickly get your system right up to date.