They shut the network down after learning that it was hacked. The hacker did not crash the network and only looked at and maybe downloaded information
No, as it is a PS3 game disc and PS2 is not compatible.
crash bash
It has a variation of the PSN. However it does not have the extensiveness that the PS3 Network has. I believe you can only do things through games. for example SOCOM, all your friends were stored on...
No just to make purchases at the Playstation store if you do not want to use your credit card