Please answer the question of the previous post: "Do you see the stutter on the preview, or only when the recording is finished?" - Either way, I suspect that maybe the jumping might be from the deinterlacing, just, maybe. If turning off deinterlacing doesn't help, try setting the FPS on your capture device's properties manually until it hopefully stops.
However if the preview looks fine, you need to tweak your Output -> Recording settings. Put the CPU Usage Preset to something faster, and lower/raise the bitrate. The higher the bitrate, the more CPU usage. If you use VBR instead of CBR, it will help you achieve a smooth recording by automatically adjusting the bitrate in case things get laggy.