Mixing DVD structure and content together?

It looks like if you are mixing few things together.
NTSC and PAL are TV standards and it depend where you live for DVD player to play those.
NTSC region player will not play PAL DVD, unless you purchased special player.
If you are in PAL region, you are luckier, because most of those players will play both formats.
DVD-R or DVD+R depend on you, what you purchased at the store.
Some players are more picky at what format they play, but from your post it looks like you are using some cheap blank DVDs to record, that is why sometime they play sometime not. and dvd ripper or dvd to mp4 will also help u gay.

The titles of the 755 How-to guides but I didn't find this.
The issue is that sometimes I try to play copied DVDs in my DVD player and it doesn't play. Anothers yes.
So I want to know wich kind of DVDs I can't play. Are NTSC? Are they PAL? Are they DVD-R or DVD+R also http://www.dicsoft.com/how-to-convert-rmvb-to-hd.html

Can anyone suggest a software that can analize the DVD and give me all the information so I can see what's happening?