I think the dribbling in PES 3 was the best yet! I played PES 3 for some time and almost stopped playing it because I felt it was too hard to get past opponents. But when I really put mind into it and had the patience to learn the dribbling, the game really opened up. It was quite rewarding to notice a drastic change in the gameplay when I suddenly learned how to avoid those tackles and go past defenders.
I was absolutely gutted when I played PES 5 for the first time. When I noticed that the side-step had been automated, it just felt wrong... And oh, I almost forgot to mention the shot-fake! In PES 3 the fake move was realistic, not that lightspeed stupid-looking thingie as it is in PES 4 and 5.