How to change shutter speed of Nikon D3100?

I have a pass to take photos at a venue in March, and was wondering how to change the shutter speed to get the photos to not blur. I can't use any flash and the light that comes on whenever you put it on any other setting except 'landscape' has to be turned off. I know how to change the ISO, I need to be able to change the shutter speed. I only have the 18mm-50mm zoom lens that came with it, and have no money for an extra lens at the moment.

So does anyone know how to change the shutter speed AND turn off that light (not the flash) Thanks!

Put the mode dial to 'S' for shutter priority mode.

Depending on what subject, if you want to "not blur", you should chose no slower than 1/30 sec for hand-held stills, or 1/80 for slowish moving subjects, 1/500 for fast moving subjects.

If you are noticing the photos come out dark, then raise the ISO accordingly.

And specifically what light are you talking about? Is it the auto-focus assistant light? Or someting on the LCD?

1) Use the camera in the manual mode
2) Set the white balance for incandescent
3) Place the ISO to 3200
4) With your 18-55 mm lenses aperture wide open (f/5.6 @ 55mm), adjust the shutter speed until you see that you have the correct exposure indicated by the cameras light meter.
5) Practice using your camera under low-light conditions until if becomes second nature to you BEFORE you attend the event

NOTE: That little light is an auto-focus assist light the camera uses to auto-focus in low light conditions. The only way to disable it is to shoot in the manual focus mode using your electronic rangefinder in the viewfinder.

Do you need the pages to look up on your user manual?

You should have plenty of time between now and the event to practice.

Now might be a good time to read the owner's manual. Details are there.