Recovering content from a dynamic disc under Server 2003

The scenario:
Me – an IT amateur running a small business with a small network on Server 2003.
Hardware – small server running 2003 with mirrored dynamic sata discs…
Problem – One drive fails and I want to copy the OS to an image to reinstall on replacement discs. BUT I don’t realise what dynamic discs are or how to manage them. Meanwhile I have installed the new discs and read up on dynamic discs and intend to go the hardware raid route. However I would still like to image the OS from the old discs and copy it onto the new ones. How can I access them on either an XP workstation or the 2003 server to do this and what method should I use?
Thanks to all, Regards, Mark