Both games are among my faves for the DS... Phoenix Wright doesn't really have much replayability, which is its major downside, but it's awesome fun the first time through!

Trauma Center is pretty sweet, too. It gets pretty dang challenging at the end, so you'll have to have quick hands to finish it. But if you play too long, your hand gets really cramped... which I suppose is Trauma Center's major downside... I recommend using a chopstick rather than the tiny DS stylus. But yea, both games are pretty awesome.