I have a horrible pad configuration which works fine for games that don't require a lot of different buttons to be used at once. I've been tinkering around with the keys but for the life of me I can't figure out how to assign the four 4-button pads (D-pad, L-analog, R-analog, and Square/Triangle/Circle/Cross) comfortably on a keyboard.
It's all personal preferences and keyboard limitations I'm afraid. Simply put, PS2 games weren't designed with a keyboard in mind, you may be better off just being a cheap $20 gamepad. Walmart has generic "ps3 compatible" wireless USB controllers for about that price that, while not exactly the best in design, will be much much better than a keyboard.
Try mine, a bit different, maybe needs a bit of training to get used to as I'm using about same config for every console emulator with keyboard to play, but I can easily play very active games that require alot of combos, depending on game ofc, but sometimes even easier than on pad.(Through maybe couse I'm generally "keyboard-player" already.)
Sometimes I help myself using scripts set under shift or something in "GlovePIE" when analogs need to be moved "around' for some stuff as this is rather difficult to do on keyboard anyway;P, also some games which use analogs to move a cam I set it closer to movement keys - but other than that this is very nice setting once you get used, especially with fighting games and standard jRPGs(FF12 is the one that gives a bit pain with camera, but both analogs in my setting can be "felt" fast as long as you ever learned to use keyboard for example for writing without looking on it, so it's not soo bad either as long as you don't want to control everything in same time).