'bout the only things I can add to Ac's comments are:
- the existing LNB is fine for FTA
if it's bad, then any Standard (or even Universal) LNB would do fine.
Best you keep the original with its matching feedhorn, if possible.
(moreso on the elliptical dishes than the round ones)
- this
site has a very simplified list of Ku satellites and programming.
It doesn't tell you the Cuba channel on 30°w has first run movies in English, with Spanish subtitles,
.. that PBS on 125°w requires an AC3 decoder for sound,
.. nor other amusing facts ...
So, you might want to camp out here and get to know the guys ('n girls) -
- and don't forget to adjust the skew of the LNB or the dish, as appropriate.