You should be able to use Windows Media Encoder to capture your screen and stream it live.
That's one option, yes.
But think about the system requirements needed to capture and encode a 1024x768 bitmap at 24fps or higher in real time.
Even if you get it to output a steady 12fps, you probably wont have any CPU% left to run any programs.
Note that you cannot stream the media unless you've got Streaming Media Services installed on an appropriate WS2003 box. Also note that this is practically impossible over a connection slower than gigabit. Unless you've managed to watch a video with 1024x768
reso over DSL, which I seriously doubt.