Mounting ISO files virtually
The following FREE tool for Windows XP allows image files to be mounted virtually as CD-ROM devices. This tool is provided here for your convenience, and is unsupported by Microsoft Product Support Services.
Virtual CD-ROM Control Panel for Windows XP:
http://download.microsoft.com/download/7/b/6/7b6abd84-7841-4978-96f5-bd58df02efa2/winxpvirtualcdcontrolpanel_21.exe
UPDATE!
I've produced a five minute webcast on how to use this free utility. You can view the webcast at:
http://www.blogcastrepository.com/WINXP/Contrib/DMcAlynn/VirtualCDDA.htm