What do you mean with MIME type?
I don't know much about Linux but it's built on different OS system than Windows. Actually, Windows is built from nothing and Linux is built on the UNIX structure. If I know correctly.
Application just means that it's "self-running" (no need to run with another application beside system32 data) isn't it?
The ms-dos executable means that it's the most common type of executables in windows. (ntoskrnl.exe, lsass.exe, krnl.exe)
I've never grub one Linux tought so I don't know what kind of executables it have. But I've heard that they are run into cell or something like that. Sounds like terminal.
Perhaps some of the Linux users could explain?