Daemon Tools - The Art of Mounting ISO Files

First off, Daemon Tools is completely free, so you don't have to worry about pay for anything.

Installing Deamon Tools Lite:

Download Link: Daemon tools Lite

Mounting an ISO File:

• Open Daemon Tools Lite 
• Double click on "Device 0: [E:] No Media" It might say something slightly different. 

• After double-clicking that icon another box will open up where you can select your ISO file. For this, as an example I will use the "RollerCoaster Tycoon" ISO file.

• After you select your ISO it will mount and the computer will think that you just put a CD in your disk drive and a setup will automatically pop up.
• All you have to do now is hit "SETUP.EXE" and the game(or whatever you are trying to mount) will install.

NOTE: Some games require the disk to be in to work, if that happens, just re-mount the ISO file before you play or use the application.

And that's it. If you have any questions or anything goes wrong simply leave a comment and I'll get back to you very quickly. Also, if you think I can change in this post to make it more clear to the people trying to learn leave a comment telling me what to improve.