Isn'y DS hard to emulate since it has two screens... and one is touch screen.... well I don't know how the emulator is going to work... its not like the GBA one..
There are a couple of Nintendo DS emulators out there, http://www.zophar.net (think that's the URL, just google it, if I'm wrong) but to actually emulate a game on the PC using the emulator's provided; very hard, but not impossible.