Just insert the disc(since a PS2 DVD is readable by normal), copy DATAZ to your PC and extract it with 7-zip or Winrar. It's a zip file.
I've found scripts, Javascripts, Java executables, Sony Computer Europe programs, conversors(one of them looks preety obvious, dds2gtf. DDS is Direct Draw Surface; you can open with photoshop, if you have the plugins. GTF maybe a PS2 texture type?)...It's all there. I didn't search everything cuz I'm lazy. There's installers in the package. I don't even know if it is possible to build Pulse again, using this progrmas, changing some stuff. Because it seems this is preety much just taking space in the disc. I can't say much, it has everything there. I just could list those things if I knew for what are they for. Also has anyone tried opening the game, removing that DATAZ, burn a DVD and test in the PS2 to see if loads faster?