If you downloaded iso file there is no need to burn it. Use ISODisk tool instead. It is a FREE and powerful ISO disk image file tool, allows you to create virtual CD/DVD driver up to 20 drivers, mount an .ISO disk image and access the files on it as if it were burned to CD or DVD. This free program can quickly create ISO image file from CD/DVD-ROM, with ISODisk, you don’t need install any other virtual drive software. Once you map the archive to a virtual drive, you can be able to view the contents in Windows Explorer.
Please note: this program can work fine with 32 bit version of Windows Vista, but it seem can’t work with 64-bit editions of Windows Vista, I don’t have Windows Vista 64-bit to test it by now.