I believe that Premiere World Sport show the wrestlemania shows, encrypted in Betacrypt, there are also some feeds available, late night and early morning on a couple of other satellites, 43 W being one of them..
There is normally (I've been told) an original language transmission with the Premiere Sport showings, I guess that they probably show boxing as well, but being a fan of neither i am not particularly up on the information. Films are certainly available, but not always with original sound.
If you are looking for an easy replacement for Sky programming, you are going to be looking for a long time, most of it is out there, but with changing encryptions and the requirement of multisat reception, it will be a relatively costly and uncertain process.
For sky one type programming in English and live boxing (inc all the Tyson fights etc) you need to be on 5 degrees east (Sirius) TV1000's show the live boxing and there are loads of other channels worth a watch including films (again in English), the downside is that you need a viacess cam and a gold card (or fun) and a programmer, codes are scattered around the internet and don't go down that often (except ticket)
Ticket consists of 8 channels, 6 up to date films, and 3 hard core mature content channels, trouble is the codes are changed sometimes twice a day, sometimes you can view for 3 or 4 days at a time before the codes go down, there is a Eurosport on there (not sure it's always in English) plus mtv and vh1 and a host of others.
There are many other film channels on there as stated, TV1000baltic, Tv1000 1 2 and 3, Cinema 1 2 and 3, all of which show films in English plus TV1000baltic and the 3 TV1000's show late night mature content, not that I ever watch them of course, cough cough.
I have a motorised dish and can get from 50 degrees east to 50 degrees west and pick up most sats, however, with a decent size dish I think (someone correct me if I'm wrong) you can have 2 lnb's set up and get astra (the stronger signal) on the offset.
It depends where you live in the UK as to what size dish you need.