I had some time to experiment last night and this is what I've learned:
Uncompressed .dmg images (made with OS 10.2.8's version of Disk Copy) can be opened or mounted and used by: Mini vMac (if the image is formatted in Mac OS Standard,) Toast 4 and 5 but not version 3, Virtual CD Imager, and DiskCopy 6.5 for Mac OS 9 as long as the image file still has the proper filetype information (it can be restored manually if lost.) ShrinkWrap can't open it.
Toast images (made with Toast 5) can indeed by opened and used by Mini vMac, BUT... at first the image was refused, although Mini vMac can initialize the image first and then use it. It occurred to me to take a DiskCopy 6 image that already works with Mini vMac, and use Toast 5 to convert it to Toast format, and it worked! I dragged it onto an open emulator window and it mounted just fine.
This is of particular interest because both of these image formats can survive a Windows environment and being zipped.



