I'm sure I'll miss many great songs, but off the top of my head:Like?
I'm going Stairway to Heaven, they're both overplayed as shit though.
The real answer would be 2112 though.
Personally I felt Stairway wasnt actually the best track on LZ4....
I do think Zep quite handily beat Queen on weight of good material as well, really I think a very small amount of filler on the first 6-7 Zep albums. You can always turn up a classic that rarely gets played...
The two greatest hits albums are probably all most people need for Queen, maybe one or two of the earlier albums.