Honestly, the DS games are easily some of the worse titles in the series. Phantom Hourglass is alright (it's pretty much Wind Waker portable). But spirit tracks was just ugh. My left handedness didn't really cause a problem, as the controls were mostly stylus based anyway, and both the d-pad and buttons did the same things. The UI can also be move over to the other side of the screen if need-be. If you think the DS games looked bad for a lefty, go look at Skyward Sword, which you hold the controller like a sword, but there's no lefty option :(. You are in for a treat though, with the Zelda games on the e-shop. The oracles and Link's Awakening are some of my favorites. Zelda 1 and 2 are a bit aged, and not all fans like those particular titles. But I still find them charming :).
I'd never heard the bit about the d-pad and buttons doing the same thing. That does make it sound a bit better. I missed out on Skyward Sword too because I didn't have the, what was it, motion plus or whatever? But I always used the wiimote with my right hand, so I might have been able to do that one anyway. I did boot up one of the Oracle games for a few minutes when I first purchased it before I had to go somewhere (what was I thinking?) and felt like a kid again. I spent so many hours on my Gameboy Color, it was nice to see graphics like that again.