I don't know the Pentax Optio but if the photographic results are blurred the problem could be either
1. you are not giving the auto-focus time to operate before taking the picture,
2. you are suffering from camera shake when taking the picture,
3. the camera (or lens) could be faulty, or
4. the lens could be cold and has steamed up. (not usual but can happen)
The following could help with the camera shake.
http://video.about.com/cameras/Avoiding-Camera-Shake.htm
With most digital cameras you can half press the taking button to allow the camera to auto focus on the main subject and then hold the button in that position until you wish to actually take the picture, then continue to press the button right down.
To test the camera, take an indoor shot with the camera resting on a solid object (table??) to avoid any shake.
I hope the above is of some help to you in curing the problem.