First game, case 4.
Although some people may disagree with me, I thought it was the most emotional case. Character development is really strong and it has a few unexpected twists. Plus it has von Karma in it, gotta love his 'Objection!' eheh. I won't spoil anything for those of you who haven't played it yet, though.
The second game was a bit weaker IMO, but still good nonetheless. Case 2 and case 4 were pretty nice. For some reason I dislike case 3, maybe because I hate clowns?
Case 4 in the first game was very emotional and rather unexpected. Especially since
Display Spoiler
Manfred Von Karma
was the murderer.
Well, actually, the fourth case tends to take place mainly in the past. Edgeworth's past. Seeing as Manfred Von Karma was his mentor and such, his father was murdered, et cetera.
Definitely the greatest case in that game. Also, Case 5 is actually an extra case added to the DS version. Back 4 years ago, in the original Phoenix Wright, they didn't include the fifth case. Now, it requires to do a lot of research with the DS stylus and your breath.:P
Comparatively amazing, if I may say so myself.
In the second Phoenix Wright game, Justice for all, the cases are generally easier than in its previous game, the original Ace Attorney, although some cases are also very frustrating at times. Usually when you've gathered a bunch of evidence and consequently don't know how to use it in the case. I've had this problem several times already.
Well, anway, as my favourite case in Justice for all, it's probably the 3rd case I fancy, unlike Beta. The one involving Moe, Maximillion Galactica and the Ringmaster, obviously. I frequently tend to consider the first 2 cases as a warm up, especially the first case. The answer is fairly obvious in the first case. And in the 2nd case, well, in JFA, it was actually harder to find out, though. Generally because of the name change Ini had. Other than that, it's frequently the person who you'd suspect the last as the murderer who actually committed the thread.