Technically speaking PAL is the superior format. But as any veteran DVD collectors know some of the early PAL stuff was garbage. Most of the variation today is down to how much care is taken during the mastering process.
Not to forget to 4% speedup with PAL - which makes me laugh because so many people complain about it - yet have no answer when they realize they have spent the entire lifes watching TV - which as far as I´m aware suffers from the same effect.
If you can do both NTSC and PAL progressive scan then you won't notice a difference between PAL P/S and NTSC P/S. The only discernible differences will be the quality of the NTSC transfer vs. the quality of the PAL transfer on the DVD.
However, if you can't do PAL P/S then you will notice that NTSC P/S will look way better than regular PAL.
(There are SO many threads about this already that you would have found the information you wanted in no time at all, if only you could have been bothered to search )