I love Freewill.
The solo is by far the best I have ever heard from any band.
When I went to the 30 yr concert last year, his hands almost caught fire
But...I still chose The Spirit of the Rado,
It is just a classic..
(its the official Rush website BGM for crying out loud!)
clearly Fly by Night -- its just another one of those classics.
I also like Tolkein, but still, fly by night is just awesome.
(I even learned it on the drums, guitar, AND bass)
2112 is an obvious pick -- thats what initially put them on the map.
But I've listened to it so many times, I started to listening to the other songs. Tears is pretty good,
but a Passage to Bangkok sounds just plain awesome.