Convert .dmg files to .iso
From Tech-Wiki
If you are trying to open .dmg files in Windows, or if you need to mount Mac OS X Server images in the new VMware Fusion, you'll be in troubble. Both of them are not compatible with .dmg files.
So you need to convert your images to .iso format, which is readable both in Windows and VMware Fusion. To achieve that, use the command bellow:
$ hdiutil convert /path/filename.dmg -format UDTO -o /path/savefile.iso