Check the following:
# '''Autofocus''' might be switched off. On the left side of the lens barrel, there's a small switch with two positions, marked '''AF''' and '''MF'''. Make sure the switch is set to '''AF'''. Note that when the switch is set to '''AF''', normally speaking the camera refuses to take a photo if it can't lock focus.
# '''Image Stabilization''' might be switched off. When you take pictures indoors without flash, shutter speed may be slow enough that any camera shake becomes visible as blur. The ''kit lens'' that comes with this camera has '''IS''' built in. It doesn't do miracles, but pics with shutter speeds as slow as 1/8 (depends a bit on how many coffees you had) come out sharp without having to use a tripod. The IS is controlled by a switch on the lens barrel, next to the AF switch. Make sure it is set to '''ON'''.