Almost all of them work on non modded PS2's
Please be specific which method to use I do not have any special disk
If you don't have any cheat discs, then try the game swapping trick. There is a list of games that are confirmed to be compatible here. Find a game that you own, then follow the guide to get Free McBoot.
Originally Posted by binavik
Gaming over USB offers approximately the same level of game compatibility.... depending on which game loader (PS2ESDL or OPL) you use.
Some games will not work over the Ethernet, so that method isn't faultless either.