Both good choices. Live Evil helped me to become the huge Sabbath/Dio fan I am now when I bought it like 20 years ago. I played that album to death and it has a very special place with me.
I don't recall owning the 'Singles' soundtrack but it was a very popular album and you couldn't go wrong with putting AIC, Soundgarden and Pearl Jam on a compliation at that time. If you were gonna do a movie about young people in Seatlle in the early 90s those three bands were the best you could pick from.
'Would?' actually was a single off the soundtrack and not off Dirt. The soundtrack came out before Dirt. Just a little fun fact for all you younglings out there.