Nikon d3100 video problems

When I record with my nikon d3100 (video), and transfer it to my computer, the quality isn't great and it plays at something like 2 frames per second so it's all jittery and stuff.

It seems that you may have unrealistic expectations. A dSLR camera is primarily a still camera with a video feature.

In the spirit of full disclosure, read this

http://www.luminous-landscape.com/reviews/camcorders/cam-cam.shtml

How much experience do you have shooting video? Do you have a good script? If shooting indoors do you have enough extra lighting so that the video can be shot using low ISO settings?

What kind of quality do you get when shooting outdoors at 1920 x 1080 (24 fps)? It should be just fine.

Actually I'd say the problem is your computer… It's probably a little older model and incapable of running the huge data stream created by HD video.

I know because I had exactly the same problem until I bought a new computer that runs at 3.3, with
8gb of ram, now all my HD video flows smoothly as it should.