Here is a intro to encoding:

http://www.microsoft.com/windows/windowsmedia/howto/articles/IntroEncoding.aspx

Do you want to record the shows for later playback or distribute them
live?  My guess is that you will want to to encode them for later playback.

In either case the basic hardware is fairly simple; a dedicated PC with
a video capture card supported by Windows Media Encoder.  (WM Encoder is
a free tool available on the MS website) This machine would be connected
to your sat. receiver's composite video and stereo audio outputs.
You'll want a machine with a fairly beefy CPU (1.5ghz or better) and a
large hard drive.  Since you'll be using local LAN delivery, you can
choose a fairly high quality (high bitrate) encoding profile.

After the shows are encoded (recorded) you can transfer the WMV files to
 your IIS machine for delivery.  You can delivery WMV files directly
from a web server IIS, but you will not get fast-forward/rewind
abilities during playback.  For this, you'll need to use Windows Media
Services.

You can run WMS on the same machine, but it is a separate service and
may not have been installed by default.  It is available for no cost.

Hope this helps -- drop me a line if you have any questions.

T.