Hi Finbar, Welcome to satellites,
There are a few online calculators that give you the correct angles to use.
Here is one:-
_www.dishpointer.com.
Heres the footprint for Astra 2D
http://www.lyngsat-maps.com/maps/astra2d.html
You should easily get it with an 80cm you are inside the footprint.
Yes, any Universal LNB will work, no special LNB is needed.
Robbo
P.S. Merged your two posts into the same thread.