Lighting issue :-s

[haha96]

Hello everyone! Okay, so I think that this question has been asked a hundred times and I am really sorry about that, but I just couldn't find a tutorial to explain it well enough to me so therefore I thought I'd ask somebody out here.
To get it started, I've got a Nikon D3100 camera and I'm having trouble with shots where the lighting is quite poor; like, for instance, when I'm in my room at night and I want to photograph something [without a tripod], the only source of light being the lightning bolt, my photo is really really shaky. I've tried switching the ISO mode to "Hi 1" which actually reduces shakiness really well, but the photo's quality turns out quite low.
I think that my issue is adjusting the shutter speed, tho I might be wrong, so I'm just wondering - would somebody PLEASE explain it to me once and for all? I don't really know how shutter speed works, nor how to adjust it, so I'd be really grateful if someone would take the time and explain that to me, or link a beginner friendly tutorial that does so (cause I myself couldn't find one). I'd also like to know what are the best settings for indoor/outdoor photographs when the light is poor, like what shutter speed or exposure to use and everything.

Thanks a lot, and sorry if this question is really silly - I'm just starting .

 

[PJL]

For night shots, you need a tripod (or some sort of solid base that's not your hands) and a remote shutter release and should use a low ISO setting. Lightning shots, especially, require pretty long exposure that you're just not going to be able to get handheld with any reliable steadiness. Cranking the ISO will allow you faster shutter speeds, but the result is really noisy pictures, which look especially crappy if most of your picture is night sky.