Caress of Steel is my favorite Rush album. I would steer you there first. The other epics are cool, but can be kinda cheesy from time to time.
I hail from Buffalo, as you know, and Buffalonians have an odd affinity for Rush. Rush is a staple there. They are from right over the border in Toronto, which is part of it I guess. I have always hated them because of how much everyone listened to it. Of course, I love to be different... so I stayed away for years. My recent home stereo upgrades have me expanding my horizons, listening critically again. I thought of how Rush did their thing and I figured they would kick ass on the system. I still have my distaste for them, but have opened up my mind, and my ears, to try to gain a different perspective. So please, bear in mind that I am not saying these will be the best albums you ever hear. But if you like musicians, you should really get off on them. If you have a kick ass system at home, you will like what they do spatially. Image, air, and staging dynamics are great on their heavy analog pressings. I think Pink Floyd did it better with their The Wall, Wish You Were Here, and Dark Side of the Moon repressings, but outside of those, and maybe Dave Matthews Under the Table and Dreaming, they dominate every other record I have.