It is not an iso, but you can create a system image with wbadmin.
And yes, it would contain all of your installed programs and can be restore even on bare metal.
If you need details on how to do it, please let me know.
If I may suggest, you could try to find the install media using "alternative" sources.
But always check the iso SHA1 to be sure it is unaltered.
You can get the SHA1 for the Windows 8.1 install media on the MSDN site...