Some of my pics are grainy

Please either post one of your pictures or explain what you mean by "lightly out pic". I don't understand.

Grainy picture is generally due to poor light conditions.....move to higher ISO.......also check the clarity of the lens

Are you shooting JPEG or RAW? Check the image quality to find out.

As it comes out of the box, Windows can't read RAW files. If you want to shoot RAW, you can download a codec from http://support.nikontech.com/app/answers/detail/a_id/13869

If you switch to JPEG, just about any graphics program in the world will be able to open your pics.

the d40 does not have live view. you would need to get a different camera.

wareseeker.com/free-nikon-d40/
or
www2.nikonusa.com/template.php?cat=1&grp=276...
or
try photoshop elements or a free program from download.com

Make sure the camera is using the appropriate focus sensor.

Does the problem occur when you focus manually?

Are you handholding the camera? Many people don't hold the camera as steady when holding it vertically. Try putting the camera on a tripod or other steady surface and see what happens.

The blue is sometimes caused by an bad CCD and ned to send it to NIKON in NY or California factory .

flash trans. is broken i want to replace if there any matching ?

2 things. make sure you are not using RAW format for your images and also make sure the pics are not too big. you can set these in the menu. :)

You are lucky for that period !!!!!. Because Nikon D40 don't have that live view option.