Someone sent me software as a single ISO file. How do I install this?
An ISO is an image of a CD or DVD disc. It contains all the data, and is often used to make multiple copies of an optical disc. You can install the software on it in one of several ways:
WinCDEmu is an open-source software that allows mounting CD/DVD images by clicking at the image files in Windows Explorer. It supports both Windows XP and Vista
it doesn't get much easier :)
WinCDEmu is open-source and freeware.
Virtual Clone Drive is the easiest to use in my opinion. It has the added benefit of being completely free.
Once you've installed it you'll see a new "virtual" CD drive appear on your machine. You'll also get a small icon in the notification area of your start menu near the clock that will look like a small silver CD. Right clicking on that will let you choose the ISO file from a location on your hard drive to your virtual CD drive. From there the virtual drive will behave just like a real disc drive.
Install the free utility http://www.slysoft.com/en/virtual-clonedrive.html then right click the ISO file to mount it as a drive like E: and then it functions just like a physical read-only drive.