Assuming there is actually a topic to be discussed here, I've got some nominees.
Sweet Home Alabama (Skynyrd) -- This is one of the most popular songs ever. Who doesn't love it (and know most, if not all, of the lyrics)?
Stairway to Heaven (Zeppelin) -- Like the Lord of the Rings, which it references, this is an epic masterpiece to which all others will be compared.
A Day in the Life (Beatles) -- The perfect blend of John and Paul.
Worlds Apart (Jars of Clay) -- I'm sure most of you have never heard this song, and it might not mean as much to a non-Christian, but this is an amazing song with complex theological themes.
I feel like there should be one more so it's five, but I can't come up with another that approaches those four for me. If I did a Mount Rushmore of great songs, I guess that would be it.