If you use the premade iso file it will most likely have incorrect IP info in it anyways. Best bet is to build your own with nero. Get the archive and use the standalone files to make your own cd with correct IP information on it.
ps2link on ps2dev.org
Some mediocre instructions on doing so with nero:
Unzip the ps2link archive wherever
in the bin dir inside the archive are all the files you will need
rename system.cnf to SYSTEM.CNF (IIRC case matters)
open IPCONFIG.DAT in a text editor like notepad and input your IP info like so: (leave the second line alone)
192.168.0.10 255.0.0.0 192.168.0.1
PS2IP DNS GATEWAY
using a dlink router with default settings mine is:
192.168.0.101 255.255.255.0 192.168.0.1
save the file and exit text editor
at this point it is also best to add a 50-100 mb dummy file to cause the usable files to move out towards the middle of the disk. Ill leave finding a dummy.bin file or creator up to you.
Open nero
New compilation of cd type
In iso tab select mode2/xa
in label tab put a label (whatever you want)
click new and you get a new empty compilation
drag and drop or add all the files from the bin dir into the root of the cd compilation (should be 9 files not in any directory on the cd+dummy.bin)
click on burn
set the speed to 4 or 8X
click on start.
when its done, you will have a working disk if you put all the files as well as the correct IP in. I have been using the disk I made with this for months, as well as the same files off the disk on my memory card.