PSX games on PS2...

[WoB]

Hi... Does anyone have a definitive answer to this...
I borrowed a backup of Harry Potter from a mate. I'm not sure if it's PAL or NTSC. If it's patched or not I don't know either. Now, I have had the same thing with other backups of mine - basically the PS2 (with Neo 2.2) recognises it as a PS game and attempts to boot it. I see the screen flicker slightly as if it's working but the PS logo screen does not appear and nothing happens.

About 70% of PS backups work OK. ANyone know why?

Would reburning make a difference?
Does patching PS games make a difference for PS2?
Do NTSC PS games work on PS2?

I tried downloading the Import Player image and burnt this to CD and it runs OK but it won't boot anything at all (I even tried games which worked OK and they didn't boot either). ANy ideas?

All suggestions greatfully received!