Camera shake. You are trying to hand hold your camera for a 1/4 of a second in the first 2 shots, and for 1/3rd of a second in the last shot and not acheiving it. All shots are taken in relatively low light scenarios.
There are 2 things that could be done... up the ISO further than the ISO 400 you had your camera set at and increase shutter speed, or place the camera on a tripod.
Hand holding below 1/64th becomes a consideration. Trying to do it for 1/4 of a second is very challenging, not many can do it without lots ofpractice and a little cheating (leaning on a wall, chair, holding their breath, proper camera holding technique, etc...).
Here is an example of a picture taken with a 0.8 second shutter speed, ISO 400 and F/4.0 aperture. It is about double the length of time of your first two pics. It was done hand-held, but I had to use every trick in the book to get it (breath control, ISO, speed, custom WB, back leaned against my backpack that leaned against a wall, proper camera holding technique and a couple other things were used to get this shot... but it WAS hand held). This was also in a VERY dark place, where candles were *almost* the main light source:
Until you get your technique down, practice, practice, practice! And to help, raise ISO, shutter speed and of course, do NOT overlook the possibility of using off camera strobes. Though the setup and techniques used in that scenario is often more complex, the results are potentially WAY more pleasing when it comes time for indoor home shots. In places like I took my shot, multiple flashes were obviously not an option.
As a final piece of advice... I would say that I would prefer a grainy shot that is in perfect focus over a "clean" picture that is blurred. You can do nothing about blur... but we have noise ninja available to nicely clean up a shot, if needed.
Good luck!
