I'd suggest getting out your camera manual and have it in your hands while you read this tutorial:
http://messageboards.ivillage.com/iv-ppphoto/?msg=5894.1
It helped me when I was struggling with other modes.
There are also some great tutorials in the locked section above - if you're not sure exactly what aperture is - there are a couple on that alone. Same for shutter speed, etc.
I found I often had to go back & forth between my manual and the tutorials. For example, the tut might say "Adjust your ISO" and then you have to use the manual to find out how that is done on YOUR camera, because all cameras are different.
Take TONS of photos. Look through our challenges section (even going way back) for some that have you try different things with the camera. Post your results, ask questions, etc. The initial learning curve can be steep and hard to climb, but once you get over that hump, it's lots of fun learning everything else there is to learn!
I'll go back and randomly pick a photo or two to give you some feedback on. Sorry, I don't really have time to do them all.