Need to mount an ISO image? Here is a simple tool from Microsoft: Virtual CD-ROM Control Panel for XP. While unsupported, it seems to work fine.
I found it on the PDC Vista Beta install disk. Looking around Microsoft's web, I found this reference to it... MSDN Subscriptions FAQ see question "What are ISO images files and how do I use them?
I was surprised to find they also linked to some 3rd party tools in the FAQ. Also, kudos to M$ for having java script on the page that worked with Firefox.