Rendering a long scene in pieces? I have a "long" scene i want to render (20 seconds). However, if i were to render it all at once it would use 90% of my computer for multiple days.Could i render it in pieces? 
Such as rendering 0-100 frames over night
then 101-200 frames the next night and so on. 
Then edit it together later.
or would there be an obvious jitter or something?
Yes, you can. Make the output file with a '.png' extension (or any other image extension) and start rendering the animation. It will render each frame as a picture and you can stop and continue it whenever you want, starting from whichever frame you want. At the end, when it's all done, just add them all in blender's video editor or in a separate video editing software and the rest is easy.

Here's a video tutorial from Blender Guru:
https://m.youtube.com/watch?v=dd5RT8rEPqU