Kind of cheating maybe, but Singles Original Soundtrack. My fav Pumpkins song (Drown), one of my fav Pearl Jam songs (State of Love and Trust), and lots of other amazing stuff in between, like those two killer Westerberg tracks, and Nearly Lost You by Screaming Trees.

If I had to only pick one grunge album, that would be the one.

Otherwise, probably Vitalogy, Bleach, or Superunknown.