Let it Come Down is what did it for me many years ago. I got really, really into that album and then everything else clicked. Looking past the music and looking into the lyrics elevated them to be one of my all time favorite bands.
I find Let It Come Down to be their least abrasive and easiest album to listen to. If you haven't tried that one give it a shot. It kind of expands on the huge Ladies and Gentlemen sound.
Pure Phase is probably my favorite behind L&G. it's a coin flip which one I like more. I LOVE the whole droning sound on that one throughout which is literally the song "Pure Phase". The last two songs are peak Spiritualized. Honestly if someone asked me what is Space Rock, I'd point them to Pure Phase. It's that genre to a T.