I am also a gigantic Queen fan and I can tell you that the true meaning of Bohemian Rhapsody has never been deduced. Freddie never really spoke about it and the rest of the guys...well, I think they just went along with him.
Roy Thomas Baker (their producer at the time) tells a great story about how Freddie came in, played the opening piano part, shut the piano and said, "now dears, this is where the opera section comes in!" and everybody was just speechless.
They recorded so many other overdubs on Bo Rhap that at one point, you could literally see through the tape they were recording on.
Anybody wanna talk more about Queen? Like I said...huge fan.