Glad that one helped. Yeah, I think Times of Grace is the most immediate, though nothing is lost through the instant power of that album. Noodles gave good examples of the two different sounds, but I'll add that Given to the Rising was probably my favorite of the post Times of Grace albums, which in a sense tried to combine the heavier elements of their older material with the less aggressive direction of their newer albums.
All of their Souls at Zero and beyond material is at least good, of course (haven't heard their very early stuff), but when I think of quintessential Neurosis it has to be Through Silver in Blood.
One of their most immediate tracks:
https://www.youtube.com/watch?v=2OeN_4ZepPE