in order for you to be able to play dvds from any region/zone you need to remove or circumvent region restrictions on both a HARDWARE and SOFTWARE level. removing region restrictions on a hardware level will allow to DRIVE to play dvds from any region without complaint or error. best way to acheive this is to flash the drive with RPC-1 firmware. 2nd best way is to use a region reset utility [if one exists for your drive model].
however, once that is done, your software dvd player, eg., powerdvd, windvd, nVidia nv-dvd 2.55, will error if it finds a region mismatch between the dvd disc and whatever region Windows has set the drive region to. best way to circumvent the software checks is with anydvd...i have tried the others, they are crap.