I have a Nikon D200 and I set my shutter speed to 1/ 8000 and the picture is extremely dark. I set the ISO to 1600 and it's still dark, PLEASE someone help me, I'm going nuts!
1/8000th of extremely fast - it would probably only be useful for fast paced sports such as horse racing or cars. Try bringing down your ISO to say 800, your aperature to f/4 or so, and your shutter to 1/200th. Now try
Your setting depends on the lighting. I can shoot at ISO 1600 at 1/640th of a second, f/2.8 and get decent shots. If the gym is dark, you'll probably have to pump it up to ISO3200 and try to get away with 1/250th if you're lucky. You'll have to have a f/2.8 lens or faster to shoot indoors, unless you have strobes.
Your'e obviously unfamiliar with the workings of this tool or any other dslr, to freeze human motion a shutter speed of 1/250-1/500th sec will be ample, read the manual, select aperture priority, pick an aperture, try not to have the lens wide open, unless its a prime, 2 stops from wide should be ok, look in the viewfinder, if shutter speed is slower than required then adjust your iso in steps till you achieve the required shutter speed, fire away.
I suggest doing some reading about 'basic exposure'. There is a good book called 'Understanding Exposure'...check it out. Shutter speed, aperture and ISO...those things combined will determine your exposure.
Also, read the manual of your camera...then read it again. It may be a lot to digest...but you can't expect to get good results if you don't know how to control it.
As mentioned, the camera has a built-in light meter that will assist you in determining what settings to use for the light you are in. It all depends on the light that you are shooing in.
1/8000 would only ever be used when shooting something extremely bright, like the sun...which I don't recommend.
one easy way of finding a base to start from, would be to put the camera into fully auto mode. Then shoot your game... take a mental note of the settings that the camera is setting. Look at the images and ask yourself how you could improve them and make adjustments in the settings to achieve this. I get the impression that you are trying to shoot a very fast game on a fully manual setting. Not a very easy thing, or something that I would reccommend. Personally I would set ISO/ASA to 200 or 400. Put the camera into Aperture priority (AV) mode and start from there. And finally...... 1/8000th of a second is very fast indeed. You would need a very fast lens and excellent light to capture anything at all...
On the D50 You hold the +/- button (next to the shutter button) and move the dial by your right thumb. I would imagine it's not much different for the D200. I wouldn't recommend full manual mode if you don't understand exposure properly. I fact to start with put the camera in sports vari-program mode - this does two major things for you:
1) sets shutter speed to fast to capture moving objects.
2) Adjusts focusing mode to continuously focus instead of fixing once focused.
I was taiught a short cut by another photographer. Unsure of f stop and shutter speed?? Put your camera in full auto, shoot, then look at your histograph. I have a 30D and I keep my histograph on ALL the time. When I look at my LCD screen I looking more for the shot's info than the actual picture. Sure helps with gettting the correct exposure.