If you have a critical eye and are into this stuff, there is no contest between a stand-alone player and the ps2. A $200 Toshiba, Panasonic, or Pioneer is a much better buy if you wanted to just watch DVDs on it.
Sony has experience in making electronics yes, but as said before; the PS2 is a gaming machine first, and a dvd player second. Nothing wrong with that, unless of course you want to say the ps2\'s dvd playback quality is equal to a $500+ player...