You could use this same method to play Wii/PS2/Xbox games on the DS through the use of emulators.
I mean if you run Dolphin(the Wii emulator) on your PC and then run Win2DS, and Viola.
Because on the PC, using a controller option called emulated Wiimote, moving the mouse up or down will be as if moving the Wiimote up and down. And moving the stylus will be as if moving the mouse, and moving the mouse will be as if moving the stylus. So moving the stylus would be indirectly moving the Wiimote.
Get my meaning!?
Then you could just set the analog stick on the nunchuk(since a lot of Wii games use it) as up, down, left and right on your keyboard and setting the D-pad on the DS to left, right, up and down would mean indirectly using the DS D-pad as the analog stick.
And then you could set A,B,X and Y to A,B,C and Z on the Wiimote and nunchuk.
On PCSX2(ps2 emulator) you could use the D-pad as the left analog stick, triangle,square,circle and cross as A,B,X and Y and Land R as L and R but you would hit a problem with the right analog stick and L2 and R2. But you're smart guys. I'm sure you can work something out.
On the cxbx(xbox emulator)the left analog stick would be the D-pad, A,B,X and Y as A,B,X and Y, L and R as L and R and once again you run into trouble with lack of buttons like D-pad and right analog stick. In addition to, the xbox emulator project was abandoned LONG ago and it is still incompatible will some games and ALL versions of Halo.
EDIT: There is another xbox emulator called xeon. This emulator runs Halo.
Mind you you must have at least these specs to run the emulators:
PCSX2(ps2)-
Minimum
Windows/Linux OS
CPU that supports SSE2 (Pentium 4 and up, Athlon64 and up)
GPU that supports Pixel Shaders 2.0
512mb RAM
Recommended
Windows Vista 32bit/64bit
CPU: Intel Core 2 Duo @ 3.2ghz or better
GPU: 8600gt or better
1gb RAM (2gb if on Vista)
Cxbx or Xeon(xbox)-
(there are two xbox emulators)
(pretty low specs.if your computer can't run it your computer REALLY SUCKS!)
Intel Pentium III processor 700MHz or faster
NVIDIA GeForce 3/Ti or ATI Radeon 8500 (for shader compatibility)
256MB Ram
Windows 2000, XP, or Vista (Only supports 32-bit OS versions)
Dolphin(Wii)-
Operating System: Microsoft Windows (2000/XP/Vista or higher) / Linux / Apple Mac OS X (Intel version).
Processor: Any Fast CPU x86 or x86_64, SSE2 supported Processor. Dual Core and SSE3, SSSE3 for more speed. Recommend a Intel Core 2 Duo @ 2.0+ Ghz or AMD Phenom 9550+ 2.2Ghz+
Graphics: Any graphics card that supports Direct3D 9 or OpenGL 2.1.
The emulators need you have to have the libraries listed below installed.
[Windows]
-MS Visual C++ Runtime 2008 SP1: This fixes the "side by side" / "application config" & model errors
Microsoft VC++ 2008 SP1 Redist x86 - For 32bit Windows
Microsoft VC++ 2008 SP1 Redist x64 - For 64bit Windows
-The DirectX March 2009 Runtime: This fixes the plugin loading errors
Note: THIS MEANS UPDATE YOUR DIRECTX EVEN IF YOU HAVE THE VERSION 9.0c or 10 or 10.1!!!!!!
Microsoft DirectX Updater
[Linux]
-install libbluetooth: fixes the "PANIC failed to load plugin Plugins/libPlugin_wiimote.so" error for linux users
You must have a video card that support OpenGL 2.x fully or Direct3D 9.0c.
Cherio!