First disregard any answers given by males (they don´t know what females want - but then, who does? For a while I thought the answer was "everything", but after trying that without success now I am back to square one. But I digress).
Next, you must find out the musical tastes of the lady in question. It will be no good playing Boulez, if she loves Chopin. Most likely though you may have to learn the last Jonas brothers hit, or the High school Musical score

. Are you sure you are ready for this kind of disappointment?

Then, it is doubtful that you will impress a lady playing the piano. Look at the composer/pianists record: Beethoven never got married, Liszt jumped from bed to bed, Chopin got entangled with George, Brahms was a bachelor... The list goes on and on.
True, Bach did all right, and Schumann too, but both married musicians, and in the case of Schumann, she played better than he.
Nah. Forget about this. Get dance lessons instead. At least you get to hold them in your arms (and they are far more impressed with a man who can tango than with a pianist - who are considered geeks anyway).
On second thoughts, you could try 4`33`` (John Cage), and kiss her while you play the piece.
And here are the threads you were looking for:
https://www.pianostreet.com/smf/index.php/topic,7635.0.html(pieces to woo the ladies)
And if you want to double your chances of getting a date (in which case disregard the first sentence in this post)

:
https://www.pianostreet.com/smf/index.php/topic,18945.0.html(pieces to woo a man)
Best wishes,
Bernhard