Noise Problem with new PowerShot S2

[Config]

Hi

I recently purchased a PowerShot S2 after having read many favorable reviews and seen quite a few pictures. But I have a lot of problems with noise in the pictures. I've got some samples I took:

(I didn't scale them down - sorry, but the noise is visible best this way):

www.n.ethz.ch/student/bschindl/IMG_0113.JPG
www.n.ethz.ch/student/bschindl/IMG_0114.JPG
(look at the countryside)
www.n.ethz.ch/student/bschindl/IMG_0004.JPG
(look at the clouds)
www.n.ethz.ch/student/bschindl/IMG_0109.JPG
www.n.ethz.ch/student/bschindl/IMG_0110.JPG
www.n.ethz.ch/student/bschindl/IMG_0111.JPG
(Here I played with some different aperture/time settings - countryside again is noisy)

I don't know - I think I'm doing something wrong because all the pictures I've seen on the net didn't have any problems with this.
I did play quite a bit with the ISO settings. The first two shots were actually made with ISO 50
Any ideas?
Thanks

[Rufford]

Yep, you've got a--small--digital noise problem. But I don't really think it's that much of an issue. I think the noise looks fairly well controled. Just try to keep the ISO as low as you can to avoid the noise.