You either burn a CD from the image (not burn the file on a CD as data, that's a different thing) or - preferably - mount it with a virtual drive so that your system reads the contents of the image as if they were on a CD drive.
Obviously, you need a special program for that.
Personally, I like Virtual Clone Drive for its' relative simplicity and ease of use.
Alcohol 52% supports more formats (like the somewhat popular MDF/MDS) but is slightly more complex.
Which of these two you pick is entirely up to you.
