For the white balance part, did you notice the grass in the one shot with WB set as sunlight appears greener? But it's not significant. The auto wb of most camera shouldn't have any problem with sunlight, that's why it looks similar. But if you try the tungstan/indesc...(how you speel that?) the different should be obvious.
Tungstan lights are yellowish, the auto wb may not be able to compensate properly for the colours, the tungstan wb settings allows the camera to compensate for this colour cast so that the picture don't look so yellowish.
The sharpness is not affected by the wb settings.
Hmmm.. for the macro shot, the problem is with the 'blur-ness' right? One thing to note for macro shots is that camera have a minimun focusing distance even when in macro mode. if the subjects is too close to the camera, the camera will not be able to focus properly and the pic will end up blur. Another thing is that during macro mode, if the magnification is very high, shakes from your hand my interfere with the focusing, resulting in inaccurate focus. Another thing is DOF, as mentioned in the other thread. he DOF when in macro mode is very shallow, so only a very small part of the subject will be in sharp focus, so you have to becareful on tghe focusing, making sure the camera is focusing on the intended part.
For your macro shot, did you notice the pot is sharp? Perhaps its because the subject is too close or the af focused on the pot instead. And remember to set to macro mode, it allows the camera to focus at subjects that are close.
Hope it helps... and that's not too scary is it?