All Final Fantasy games. But lately I've been stuck on the Naruto games for DS and PSP and I'm waiting to get my hands on the ds one though the PSP looks way better with being able to use the Akatsuki characters so that should be fun. Unless it's Kisame because that guy is really slow and Itachi is just fun to use because he's normaly faster then everyone, but give me someone else and I wouldn't mind seeing if I could control them.
Well Final Fantasy if that's considered.
I also like Pokemon from GB to NDS
Medabots also was great. Always loved that Rukusho head.
Naruto Narutimate/Ultimate Ninja series isn't that difficult especially on insane mode XD Really like the fighting on the game.
I have only played Gundam Battle Assault 2 on PS2 so yeah I liked that one too.
.hack// series isn't to be forgotten also haha! I only had .hack//Quaratine for my PS2 though.
Dragon Ball Bodokai Tenkaichi is also good. I've played all of the 3. Yay for the most difficult mode. I just can't collect all capsules though haha XD
I have played that Japanese Bleach game on the PS2 too(I have it). Seems pretty good. I just like it when I go Bankai XD