To use Virtual Reality in FSX you need to install a program called Flyinside. This alone is an incredible experience. The program also allows you to import any window. So I imported a video and it works really well. I have loads of training videos and I used to use multi monitors to fly the simulation and watch the videos at the same time. This though allows you to watch the video from within the cockpit.
I made a very short video to try to demonstrate this.
It’s always hard to get across just how good it is to actually feel like you are sitting there inside the actual cockpit. The sensation is something I thought I would never experience. It also makes everything easier. Turning switches, setting flaps, reading the dials all enhanced. When I fly and look out of the window in a turn, you get that vertigo sensation in your stomach. The inner ear is being tricked so well it has a physical impact on your senses.