I just downloaded the PS2 linux iso image from sourceforge and burnt it to a DVD in my laptop's DVD burner. I can play the resulting video disk on my laptop using Windows media player but it does not play on the PS2 (I get a 'TV system doesn't match' message on my TV). My DVD player won't play it either, so I think the DVD is genuinely non-playable (e.g. perhaps a PAL DVD)
For completeness's sake, the model number of my PS2 is SCPH-90001 CB, purchased in the USA.