The problem in the photos is clearly the ISO setting. You're using a camera that is now 5 years old and has a small sensor (relatively speaking) and it just doesn't do ISO 400 very well. (Most P&S don't do ISO very 400 well...) Check out this photo in the review on Imaging Resource:
http://www.imaging-resource.com/PRODS/D550/D55FAR400.HTMGenerally, the point and shoot cameras don't do as well as the DSLRs in the noise department at higher ISO ratings.
From dpreview.com:
QUOTE
ISO equivalence on a digital camera is the ability to increase the sensitivity of the sensor. This works by turning up the "volume" (gain) on the sensor's signal amplifiers (remember the sensor is an analogue device). By amplifying the signal you also amplify the noise which becomes more visible at higher ISO's. Many modern cameras also employ noise reduction and / or sharpness reduction at higher sensitivities.
....With tiny, high pixel count chips noise is always going to be an issue, and to a large degree this is more a test of the effectiveness (both measurable and visible) of a camera's noise reduction system. Designers have to balance the desire to produce smooth, clean results with the need to retain as much detail as possible (if you blur away the noise, you blur away image detail too). These crops show that all manufacturers find it difficult to produce an acceptable result at anything over base ISO from 10 million pixels crammed into a tiny sensor.
Unfortunately, your camera was never reviewed at dpreview, so you can't see how it does in their very good noise tests, but in just quickly perusing the reviews of various cameras that are reviewed, it becomes pretty clear that when it comes to noise, you more or less get what you pay for.
Check out the review for the
Nikon D40 for instance. Then compare it to say, the
Nikon P5000 Both are 10MP cameras, but the difference in noise levels is pretty striking.
Clearly, choosing the ISO setting yourself is key - at least you then know what you're going to get. You might even want to run your own comparisons in a couple of different lighting conditions to figure out what you find acceptable with YOUR camera, if Phil Askey hasn't already done it for you at dpreview.com.
(BTW, SB, your camera in the UK was the 300Z...I don't know why some manufacturers persist in confusing us with different naming schemes in different markets!!)