DICOM datasets have many elements one of them is called "Pixel data" (NOT all datasets have this element) which contains the image(s).
If your requirement is to just extract/convert the DICOM images to other formats, you can probably find a small code to help you extract the images or you can use a free library to do that such as: http://opendicom.sourceforge.net/
If you want to do more with the DICOM dataset, you will probably need to read more into DICOM and do some research. For example, in our case we did the research for transferring and displaying the DICOM datasets while being under still time frame so we used a library to help facilitate those things called leadtools and it helped us.
It all comes to what your requirements are.