The preview animation will be dependent on the power of your computer. The more powerful the smoother and faster it will be. There is also a frame rate setting in the keyframe editor. The rendered animation will primarily be dependent on the frame rate you set in the render setting. This nay be different to the one on the keyframe editor.

"I realize Poser isnt very good for animations"

I would disagree. Specifically what is it that you are not able to do in it?