Keeping image on LCD screen

That feature is called "Live View". The K100D camera does not support that feature.

More specification information can be found here

Regards,
Jacob

The best way to lighten the viewfinder is to purchase a new focusing screen. There are many alternatives available and usually cost around $100. There are specialty screens to allow better manual focusing and others that brighten the viewfinder. These effects are usually achieved through coatings on the screen. They are relatively simple to install, however if you are uncomfortable doing it yourself, a local camera shop should be able to do it in a matter of minutes.
This screen will allow better focusing of manual lenses and will also brighten the viewfinder, when you purchase the "Brightness enhancement treatment" option at the bottom of the page. http://www.katzeyeoptics.com/item--Pentax-K100D-K110D-K200D-K-r-K-x-Focusing-Screen--prod_K100D.html
The linked product also fits your camera, and the brand is highly regarded as being good quality. There are other options available though, simply search on B&H Photo Video or Adorama Camera. They have many different options.
B&H:http://www.bhphotovideo.com/c/search?Ntt=k100d+focusing+screen&N=0&InitialSearch=yes Adorama:http://www.adorama.com/SearchSite/Default.aspx?searchinfo=focusing+screen&category=4294962858
Thank you for choosing FixYa!

I suspect dirty contacts on either lens or body. Clean contacts. Should alleviate problem. This happened to my K100d.

You can download a manual from the support section of the Pentax website.

No... that camera (same as mine) does not have that feature.
Practice viewing the picture as soon as you take it. You'll get used to it.

If you want to "test" the shot and not save the pic, then instead of pressing the shutter switch, move the on/off switch past the "ON" position (it is spring-loaded and will return to the "ON" position).

Pentax K100D does not have Live View function. So you can't preview the image before taking the image.

Read the K100D manual. Go to the Setup menu and allow for lenses with manual aperture settings.

ON digital slr cameras there is no pic framing on the LCD display.

This is called "Live View" and it is not possible with the K100D. For that, you must purchase one of the more recent models. I don't think the K200D has it yet, but I believe the K20D has it. (Don't quote me on that.)

My buddy just got it with his new Canon Digital Rebel XTsi? Not sure what the model is.

My solution to this (with my K100D) is just take lots and lots of shots. Hopefully one of them turns out to be a keeper!

That's how the professionals used to do it with film and no preview (during or after).

Take care & Happing Imaging!
Glen
:)

The interface IC ( between the main CPU and the CCD sensor ) seems faulty . Camera should go to the Pentax agents unfortunately.