This dialogue allows you to specify the properties of the video that is streamed. You can select a codec to improve the quality or to decrease the band-with required to view the video.
You can select a range of possible compression codecs for the video here. These control how the video is streamed and heavily affect the bandwidth of the output video and also the quality of the output. These codec come pre-installed in Windows and also depend on the version of 'Windows Media Player' you have installed.
This setting affects the bandwidth and quality of the video. The higher bandwidth the better the appearance of the video.
For camera output you can view the camera using a series of jpg images. Here you can select the quality of the jpg, smaller values decrease the band-width and the clarity of the image. Higher values the opposite.
This is the number of frames per second that will be displayed in the video/jpg stream. For a full movie quality this is normally 24 FPS (TV is either 25 or 30 depending on your country). Anything below 24 frames will star appearing jerky and below 10 very much so. There is no real reason to increase the frame rate above 24 (or 25/30 for TV).