Your request is contradictory in that an ISO file is an "image" file. You
can either burn this to media like a CD or DVD, or you get software that
allows you to mount these as virtual disk drives. On some occasions, you
will find that software will refuse to install from a mounted image and
you'll have no choice by to burn to media. For instance, I found that I
could not install Visual Studio 2008 from a mounted image and had to burn
the ISO image to media. You should be able to find free software for ISO
image burning.