Having trouble with an screen recording saved as AVI from Rylstim Screen Recorder
The video may look choppy because of the codec you're using. For fun, I recommend trying out your h.264 variant, x264vfw. I know that h.264 is almost ubiquitously used for internet content. 

Playback in premiere is extremely variable when it comes to sequence settings, video preview settings, system preferences (such as scratch discs, and optimizing for memory consumption/performance) and also what type of hardware you have (Nvidia GPUs mercury playback v.s. AMDs OpenCL). I recommend checking out this guide on optimizing your premiere experience: http://blogs.adobe.com/aftereffects/2011/02/optimizing-for-performance-adobe-premiere-pro-and-after-effects.html