Before I'm gonna buy a Wii on November 16. with Mario Galaxy, there's 2 things I'd like to know about the Wii.

I have noticed that if you aren't in a good line of site the hand in the Wii menu will jump around. There's definitely a sweet area that the wiimote wants to be in. This is no problem when you are standing directly in front of the tv (up to 15 feet away if you prefer) but at certain angles the sensor bar gets finicky.

As far as the "point at the bottom of the tv" I would assume that your friend has the settings on his wii dialed in incorrectly. There is an option to tell the wii whether you are placing the sensor bar on top of the tv or below it. He probably has that option toggled for above. Also, make sure there are no obstructions in the line of sight from the sensor bar to the wiimotes.

I have never noticed lag...period.

The issues with the wii, the sensor bar, and the wiimote are, IMO, software problems.

Case in point: the hand on the wii menu can tend to be a bit shaky...conversely, the reticule used in Metroid Prime and even the Metroid Prime Demo channel is smooth as butter.

After you get it setup maybe you can offer your analysis. It would be nice to see if after you set it up yourself if you notice any of these problems.

Yeah, he probably has it set up wrong so that pointing below the screen seems like pointing at the screen.

I noticed lag with the classic controller when I first got it when I play Super mario World, but oddly enough it's gone now. I'm not sure what was up with that, but it was definately noticeable at first, but now there's none. I'm not sure what changed or what happened, but it works fine for me now.

Seconding the fact that it sounds like your friend had the sensor bar set up improperly. I can manage pretty precise aiming on mine, after I spent about 5 minutes or so centering and configuring it.

I haven't noticed any lag with the classic controller. For reference, I was playing that "quick draw" minigame in Kirby's Adventure this morning, and I beat it easily. That requires pretty precise timing.

Well, there is no problem with a shaky pointer, and there are no obstructions or whatever. I'm pretty sure we've got the settings right, too - we set up the Wii together, and tried both positions (on top & below) with the correct settings.
it's a bit subtle, but you can try it with two people: One of you holds the Wiimote so that the pointer is in the center of the screen, and the other looks from the side - you'll notice that if you draw an "invisible extension", the Wiimote is actually pointing at the sensor bar, not at the center of the screen. Or maybe not, but it was the case with our system.

About the lag: It was very noticeable, made me play much worse for a few minutes, then I got used to it. Gotta say that I'm very sensitive when it comes to latency issues; must be the years of making music with Logic Audio and software synthesizers.

It's possible for a game to calibrate the pointer (Zelda does it) but most games haven't bothered yet since it's usually "good enough" acting as a 3d-mouse instead of a true one-to-one pointer.

Haven't noticed any lag, could be your TV?

If there's lag, it's probably the TV. A lot of TVs do some image processing that delays the picture; this is why games like Guitar Hero have calibration. My girlfriend's TV has a delay of 116 ms. See if your friend's TV has a "game mode" where it disables the video processing to eliminate lag.

Most games don't have poitner calibration as DK mentioned, so your movements may be exaggerated on a large TV. It's very easy to get used to though, because it's very precise, and you can always see the pointer move on the screen.

We had the problem with Wii Play in my old web design class. We had the sensor bar set properly. The problem is that the IR beams aren't wide enough to hit 4 people with a 3 foot gap between each other 10 feet in front of it.

I had a lag issue until I changed my setting to GameMode.   I didn't even notice it until I had trouble with the timed button pressing in RE4 and catching a fish in Animal Crossing. 

My friend's TV has horrible lag...it's likely the TV...

Anyway, I just played Super Mario Galaxy at Gamestop, and the pointer precision was quite good, and it was pretty sensitive, but that's probably because I was pretty close to the TV. Worked great though...no problems with controls whatsoever.