A good place to start is Kodak's "Joy of Photography". it will have the basics on aperture and shutter speeds, ISO, etc.
You might also find www.nyip.com interesting and informative.

Only an understanding of the basics of photography will give you this - and most of the answers will become obvious then. Knowing the fundamentals, one can reason out the settings for any situation.

The best book I have ever seen to get you started, is "The Camera" from Time-Life Books. This is part of a series that was published in the early 1970s. Fundamentals such as shutter, lens and film speed are clearly described and even more clearly illustrated. (For digital, just substitute ISO setting for film speed.) Lens focal lengths, depth of field, and using settings for creative control are exhaustively covered.

It also has an excellent history of photography and is richly illustrated with some of the greatest photography of all time as a source of inspiration and deeper understanding of the photographic art.

Many sets were sold, and they are frequently to be found in used book stores and from time to time on Amazon.com. The "Joy of Photography" from Kodak has also been highly recommended.

"The 123 of Digital Imaging" is a contemporary CD-ROM with lots of good information. While the two books cover the fundamentals of photography, both were published prior to digital cameras. The CD deals only with digital imaging. The information is there, but it is not nearly as clear as with the Time-Life book. However it does cover image processing, printing and similar topics.

You might also look for community-based introductory courses.

Once the fundamentals are understood, then it is a matter of gaining experience. Digital cameras are great learning tools, since you can view the image seconds after the exposure was made, and see what effect a change of settings has on your image.

At the root of every image is an understanding of how shutter, aperture and ISO work together to give perfect exposure, but more so, how each of these three fundamental elements impacts the image itself. Second is an understanding of the nature of lens focal lengths and how they determine the feeling of the image. Of course they are completely linked to the exposure equation.

When you understand these, everything else pretty much falls into place and from that point it is a matter of refinement. However, until you understand the basic fundamental principles upon which photography is based, suggesting settings is meaningless.