Disk Image from Mac OS 9Apple's Disk Utility should be able to open it, and a double click should do this. If the disk image is damaged and will not mount, File Juicer may recover some of the files from it.
GEM Bitmap file formatGraphic Converter from Lemke Software can convert it.
IMG Disk Image file format used on WindowsThey may work on MacOS X 10.4 just by doubleclicking on them. Perhaps a rename from .img to .iso can help with this.
I have little experience with such disk images and I would expect File Juicer to be of limited use. If you have access to Windows, MagicISO, IsoBuster or Roxio's Easy Media Creator can handle them.
Because .img files are "raw" dumps of the contents of a disk, File Juicer should be able to extract JPEG, MP3 and the other formats shown in the preferences. This is as always if they have not been encryped. File names, folder structures and other file types are not extracted.