No it's not scart, that's just a composite cable connected to a scart adapter, it doesn't magically change the wiring, that's why it shows up black and white for you.I tried playing some US PS1 games through PS3 on a CRT and all I got was black and white colors. My cable looks like three cables and it goes towards a scart thingie. Does that mean it isn't really scart?
You need to get one with the scart head instead, there are cheaper Chinese ones out there, not great as some of them show some noise in the picture, though it's totally up to you..
I would recommend using a component cable, OEM preferably, either ones included with the PS2 or PS3 they're basically the same, either your tv has component inputs or not you can get a component to scart adapter, the only you need to worry about is the audio wires can't plug in said adapter and you need to either plug them into a receiver, or an cheap external DAC, or get one of these with an extender cable to connect with headphones..