AnyDVD and DVDFab should have removed the region coding. This is very unusual. Those would have been my first suggestions.
Have you tried the dvd player hacks found here? http://www.videohelp.com/dvdhacks/sony-dvp-ns50p/5927
If none of those hacks work, I have a solution for you but I don’t think you’ll like it much. You can rip just the main movie to the hard drive (use either DVDFab HD Decrypter or AnyDVD + DVDShrink in ReAuthor mode). Then use Vob2Mpg to convert the .vob files to one big mpeg2 file. This won’t degrade the picture, you’re just removing the video from the dvd structure. Then rebuild your movie with an authoring program. Import the newly made mpeg2 to DVDStyler, GUIforDVDAuthor or DVDAuthorGUI and make a new dvd-video. Burn to disk. It will not have any region coding.
You lose the old menus, the extras, all the old structure this way. If you want to rebuild the entire thing…that is possible, but complex.
Lets hope someone else has a simpler solution and posts.