If you're looking to play some PS1 games, then you may want to check out some of the PS1 Emulators for the PC...
The one I useis ePSXe... Website here.. http://www.epsxe.com/ Read the directions, and you will have no problems...
But, if you're strictly asking if it's possible to play a back up on a regular ps2 without any mods, I Don't know, but I'm gonna guess no...
Hope I was helpful...
Cheers
No you do not need a gameshark, psx boot disk or any of that to play psx backups. Theres another method called the swap methods. Theres 3 of them and all you need is an original psx game to do it. Ill give you the link to the site once I find it.
i like epsxe, the only problem is none of my computers are good enough to play them, the framerate gets too low, and it looks like crap. please notify me when you find the site