How to mount an ISO image in Windows Vista
The freeware utility from Microsoft to mount ISO Images doesn't work in Windows Vista. Thankfully there's another utility that does.
The utility that we will use is called Virtual Clone Drive. This utility will let you mount .ISO, .CCD, .DVD, .IMG, .UDF and .BIN files. Download the utility and start the setup process.
Select Yes or OK at the hardware prompt and continue. You might have to restart your computer. Now you should be able to mount any ISO image by just double-clicking on the file. Note: If you are going to reinstall this utility, make sure you uninstall it first, or you'll BSOD yourself repeatedly.
This utility does not work on Windows Vista 64 bit edition.
Alternatives
Virtual CD-ROM (Microsoft) - This utility does not work in Windows Vista
MagicDisk - This is a nice, free utility, but it isn't very easy to install in Vista64.
Alcohol 52% - Free version of Alcohol 120, but it bundles a browser toolbar that they claim isn't spyware. It's unacceptable.
Daemon Tools - Well known tool, but the latest version installs spyware on your computer, and the old version doesn't work in Vista.
At this point, Virtual CloneDrive is by far my favorite free utility.
Download Virtual CloneDrive from slysoft.com