Then the lag between the wiimote and the console is acceptable.The Wiimote's traditional controls - the "plus" pad, the analog stick, the buttons - all seem to be utilizing the same, effectively latency-free wireless technology utilized by the Gamecube Wavebird controller. There is no detectable lag.
I doubt this is caused by lag in the wireless connection at all as you have said yourself, the other buttons work fine. Rather, the delay is likely there purposefully. In the case of the system menus or other pointing functions, it is likely there to reduce unnecessary jittering of the cursor. A mouse can be set still, but a pointer is still being held by a human hand and not perfectly still. In the case of gesture recognition like in Wii Sports, it needs to take the time to let you finish your gesture, or at least complete more of it.These phenomena are observable, and identical, in both Wii Sports and the Wii's built-in default system menus. Considering the well-established latency issues related to infrared technology, there is little wonder that such phenomena are observed.