Just be advised NMM's compatibility is pretty low right now, from what I can tell. I don't think there's a compatibility list for it, but here are a few games it works/doesn't work with, just to give you an idea:
All games listed here are NTSC/US.
Super Mario Sunshine: Works
Mario Kart: Double Dash!!: Doesn't work(Hangs the console if NMM is enabled)
F-Zero GX: Works
The Legend of Zelda: Wind Waker: Works
The Legend of Zelda: Four Swords Adventures: Works
Phantasy Star Online Episode I & II: Doesn't work(Asks for a memory card to be inserted in Slot A, even if NMM is enabled)
Ikaruga: Works
Paper Mario: The Thousand Year Door: Works