Deciding which version to get largely depends on what purpose they will serve. The "Melody Line with Piano Accomp." is just that. So, if these songs were to be used for mostly audition/solo settings, that one would be your better bet as the pianist would have a more accurate orchestral reduction to play underneath your melody. Otherwise, if you yourself are the pianist, the straight (and much more common) "Piano/Vocal Selections" might be the better choice since it includes a (most likely) simpler accompaniment part with an incorporated melody (although, some argue that tying the melody into the accompaniment actually makes the latter version MORE difficult; ah, well, that factor depends entirely on the specific score).
...And so, there I was at the stage door for "Equus". The enthused avalanche of "Harry Potter" fans was literally pushing me into the barricades. As I was thrust face-first into Daniel Radcliffe's hat, I suddenly felt the thumb of a lanky gentleman behind me pressing firmly into my back. It was then that I realized that both of his hands had Playbills, and that both arms were outstretched in front of me...
