Dan Fogelberg: Greatest Hits. (Epic QE 38308.) Dan Fogelberg has a way with lyrics. For the last nine years he has been giving his listeners poetic lyrics and moving melodies, all with a tender, lilting voice. Now he has released (as most established artists do) a greatest hits package, with eight previously released songs and two new ones. In recent years the folk sound captured in his early albums has become a more pop-rock one, and this is evident on this record, which contains only one song from his early albums (the bouncy, uplifting ''Part of the Plan''). All the others are relatively recent, very recognizable recordings. One of the albums most beautiful songs is ''Leader of the Band,'' which Fogelberg wrote for his father. The two previously unreleased cuts, ''Make Love Stay'' and ''Missing You'' are classic Fogelberg - that perfect combination of acoustic and electric guitar, sweet melodies, and polished lyrics.