I love Kingdom Hearts I and II, but sadly the PS2 that I have reads DRE's about every time I try to load them now. (but it loads a scooby doo game just fine) I only borrowed the PS2 for KH. But I was able to get them read enough that I finished both games luckily.
Then my DS is another story, I finished 358/2 days (on beginner mode XD) and Xion was so hard to beat. I found Xion hard in Agrabah for some reason. But I beat her, and the ending was epic
Kingdom Hearts and Mario are the only games I pretty much play.