I want a new digital camera! But I don't know what is the difference in the models?

Like point & shoot, SLR, etc. Is there a better brand? Canon, Olympus, Nikon, Pentax, Samsung, etc? Do mega-pixels determine the quality of the pic? I like taking nature pics. I also have children who are active in sports and I attend many professional sporting events throughout the year and like to take pics of the action. So I want something that will take unblurry pics at high speed but isn't overly heavy or bulky? Any suggestions?

Since you know almost nothing… Get a compact… Start at the bottom, learn the basics… Once you have those down, THEN upgrade to a bridge camera…