IR lasers are very expensive. AND they seem like a good idea at first but it's almost impossible to write with one. Besides, if you just use Smoothboard in presenter mode you get a laser pointer like effect. If you really need to see a red dot you can change your mouse pointer graphic to a red laser dot.
Regarding the issue of not being able to see the laser, it could probably be overcome by pairing the invisible IR laser with a visible red laser. The two would have to be as close to each other as possible and parallel so that the red dot would show you almost exactly where the IR laser dot was and the Wii mote would hapilly see a 940 nm wavelength dot.
I hope this helps.
James McLain
Whalebone IR and Software