Passcape ISO Burner is a free application specifically designed to allow you to burn bootable discs out of an existing ISO file. However, it can certainly be used to burn to CD or DVD any ISO image file stored in your drives. The program will also help you to create a bootable USB disc and to unpack the files contained in the ISO image.
There is nothing much to add when it comes to functionality, except for the possibility of using an external burning program to create your discs. In fact, what this option does is to unpack the ISO image so that you can then use any standard disc-burning application with no ISO burning capabilities. As for the interface, they do not come much simpler than this one, but it merely reflects the simplicity of the tool itself. It is so simple that it requires no installation, and becomes fully functional just by executing the EXE file included in the ZIP file.
The program will actually inform you that no bootable specification has been found whenever you load an ISO file whose content does not include the expected files, but this warning will not stop it from burning whatever ISO file you wish to transfer to CD or DVD.
All in all, not an incredibly useful application, as the functionality it offers will be probably already available in whatever disc burning application you have installed in your system, but being a free and easy-to-use utility, it is – at least – worth knowing that it exists.