Daemon Tools is a really good application which can make your PC/Notebook have a virtual DVD Devices. It's work really efficient and faster for doing some installation proses that need DVD. Using DVD will spend lot of time because, it spent lot of time when reading, processing and copying the data. DVD will not have a long lifetime and it the data inside the DVD will be corrupted faster by the time goes on.
Creating an image(extension such nrg, iso and etc) is a solution to back up your DVD file. Some websites and companies have shared their Operating System product with Image Iso File. For example windows 8.1 preview, ubuntu, backtrack and many more are sharing their download link to download the Operating system ISO file.
With Daemon Tools we can mount the image easily and faster, without spending much time to extract it with WinRar/Zip. You can download Daemontools Here