A folder of images burned on my 10.2 Mac would mount, but not open, on my Win2K Pro machine. I have done this quite a bit under 10.1.x, so I know it used to work. It no longer works. Ergo, it's broken. The files are not corrupt, the burn was done the same way 100 previous burns were done, Jaguar was a "clean install", etc.
Very clearly, something in the change from pure ISO9660 to HFS+/ISO9660 has caused some sort of issues with some (but not all) Windows machines.
I forgot to bring my trial burn into the office today to see if my work laptop (also Win2K) would read it.
-rob.