Extract files as MacBinary files
Apple Mac files usually exist out of two physical files, the "Data Fork" and the "Resource Fork". These two files have an identical file-name and are shown by the Mac OS as only one file. This causes problems on Windows systems because two different files with same name in one directory are not allowed. IsoBuster shows these 'combined' files also as only one file and when you extract them with IsoBuster, IsoBuster extracts the file(s) so that Windows can handle the data content. Should you want to take these files back to a Mac later on then you will notice that the Mac can still handle them however the automatic link with a program may be gone. E.g. if the file is a word document, clicking the file on the Mac OS may not launch your Word editor anymore, however, when you start the editor and select "Open File" you can continue the work.
If you extract the files as MacBinary files however, IsoBuster combines the two forks into one file according to an existing standard, the MacBinary standard. The resulting files are not much useful under Windows and you should not extract as MacBinary files if you intend to use the files on a Windows system (*). However if you intend to transfer the files to Mac via email or network or ... then extracting as MacBinary files may prove useful. For Mac there are several programs that can handle MacBinary files and they re-create the two resource forks from the one MacBinary file. Stuffit Expander for instance does this.
(*) If you don't just Extract but instead choose Run or Extract and Run the files will never be extracted as MacBinary, even when the option is set, because Run implies you want to execute the file on a Windows system and on Windows systems MacBinary files are not much useful.