For all of you intereseted in the PAL/NTSC thing, this is a good article for the non technical of out there
http://www.michaeldvd.com.au/Articles/PALvsNTSC/PALvsNTSC.asp
On the topic of the 4% speedup, I run all my DVD's through a PC with reclock, so PAL ones run at 24fps (@ 72Hz) with the correct sound, for that pitch perfect movie watching experience.