Windows update from cd?

To use windows update you visit the website, select scan your system and download any relevent updates which are then installed for you.
My question is:
I have customers who have no internet access or are using very slow dial-up connections and toobtain all windows updates would take many hours. I can download all available updates for windows from the corperate site and write these to a CD. Is there an easy way to install these updates on my customers computer, rather than applying each update individually is there a way to configure windows update to run and scan but pull the updates from a CD? If I have to install updates by manually opening each update does the computer have to restarted after each update or can all the update files be opened with a restart at the end?
Thanks