Well, the zapper games do indeed work on the NES emulator for Wii! And yes, they do have a crosshairs. But, it is really hard to get the hang of it. There's kind of a lag in moving the crosshairs around.
The good news is that I also got the SNES emulator working while I was in there goofing off, and that's awesome too.
Anyways, here's my first try. 23.000. As soon as you have to shoot two criminals, the slow crosshairs become a huge detriment.