Can I buy a PS3 in Poland and will it work with bluray discs from Australia (both PAL countrys)?

Question

And what is the difference between hardware and software ps2 backward compatibility? Do ps2 games still work with the 80GB ps3?

Are only bluray movies encoded and restricted by PAL or NTSC or are games affected too?

Answer 1

Yes, Blu-Ray is Region Free! It can be played on both PAL & NTSC!

1). 20GB has no chrome trim, no memory card reader and no wi-fi. Not manufactured anymore. Has the best backwards compatibility with PS2 games due to Emotion Engine (PS2's CPU) and Graphics Synthesizer (PS2's GPU) installed.
2). NTSC 60GB has the same backwards compatibility as 20GB versio, also has memory card reader and wi-fi. Has a chrome trim.
3). 80GB - extended memory, but reduced backwards compatibility with PS2 games, it has only Graphics Synthesizer (PS2's GPU). Around 80% of PS2 games can be played. Available only in NTSC regions.
4). 40GB - can't play PS2 games at all (all PS2 chips were removed), has 2 USBs instead of 4, no memory card reader, has wi-fi. Avalable in black and white colors. White is on sale only in Japan. Uses 65nm technology (lower power consumption). Improved cooling system.
5). PAL 60GB - reduced backwards compatibility with PS2 games. it has only Graphics Synthesizer (PS2's GPU). Around 80% of PS2 games can be played.

Answer 2

POLONIVS, report Drake's answer, please, originally, it's my answer, he stole it! Thank you.

As for your question - PS3 games are region free. You'll be able to run PS1/2 games as well. As for movies - each region is divided on zones (I think 6 per each region - check if Poland and Australia are from the same number).