I thought it was obvious.
Since there is no iso, you can do these options.
1. Make a cd image and save that as a *.iso file..
2. Just burn those files to a DVD-R...
Technically, you have all the files, you don't necessarily need to put them in *.iso format. (Which is just an 'image' of a dvd containing those files... it's the same as if you just burned 'em to a DVD-R)..
Finally, in order to play the game on your PS2, you must have a mod chip installed..
(At the very least!)
The easiest thing is to use something like SwapMagic, which should let you run the burned DVD in your ps2.
That's it.
You don't have to create an iso image. I just thought you might have been wanting to emulate the game on your computer.. xD
~~Azurith
PS> Don't even try to burn it to a CD-R...