Secondly, I've been taking pictures with people outside a movie theatre and noticed that when it's dart the shutter speed is SUPER slow. Is there any way I can have a normal shutter speed to take a decent picture in the night time? I also plan to take photos of bands and you know most gigs are in a darker setting, so I know it's going to be a problem.
#1. "RE: how do I get more vivid colors and shutter speed in dark places" In response to Reply # 0
The three things that control exposure are the shutter speed, lens aperture (f/stop), and ISO. The less light there is the slower the shutter speed, the wider the aperture, or the higher the ISO needs to be, or all three. If you're using the "kit" lens that came with your camera, chances are it isn't very "fast" meaning it's maximum (widest) aperture is not very big, so it can't let in as much light. To obtain a correct exposure, the shutter speed has to slow down and/or you need to increase the ISO to increase the "sensitivity" of the sensor to light. Faster lenses (with wider maximum apertures) are useful in dim light, e.g. 50mm f/1.8, 35mm f/1.8 or a fast zoom such as Nikon's f/2.8 models.
When dealing with slow shutter speeds, a tripod is recommended, if your subjects are still, anyway.
As far as the vividness of images, either change the settings in the camera to "vivid" or alter the saturation in post processing, e.g. Photoshop.