I have a Nikon D90--not sure how different the setting might be for you, Katkoota, but there is an S setting on the dial that stands for shutter speed. If I put my camera in 'S' mode, it allows me to pre-set the shutter speed. The camera still takes care of the focus, ISO and the aperture. If the light is low, you may need to bump up the ISO a bit (which is a separate setting on my camera--I have to do that through the menu). Still, I've found that if the shutter speed is faster than 1/800, I need a really bright sunny day to get a good image, even at higher ISOs. I'm primarily using a longer zoom lens with a fairly small max aperture--if your aperture is larger you can push the envelope a little more...
"We are--each of us--dying; it's how we live in the meantime that makes the difference."
"It's not what you gather, but what you scatter that tells what kind of life you have lived!"
"Be kinder than necessary, for everyone you meet is fighting some kind of battle."