This has been covered before here, try a search you may be able to find the thread. Failing that, you need to do a couple of things, make your DVD ROM region free this can be done by changing the firmware of the drive, have a look here
VCD help also try a search for firmware in google for other sites.
You will also need a software player that will allow this.
I use a pioneer DVD rom with upgraded firmware and also a realmagic hollywood+ decoder card with appropriate region free playing software.
Bear in mind if you change the firmware of your drive it will be out of warranty.