It was my impression that most PAL dvd players can handle NTSC dvds without problems. You may be running into a region code restriction, since US dvds are region 1 and you are in region 2.
You might be able to hack your current dvd player and make it region free. Look up the model at videohelp.com http://www.videohelp.com/dvdhacks
If your player isn’t one that can be modified, you might look for a relatively inexpensive player like the Philips 5982 which can handle both NTSC and PAL, and is easy to make region free: http://www.videohelp.com/dvdhacks?dvdplayer=5982&hits=50&Search=Search