Simple, Stylish Songs for Piano

I would like to surprise my wife by singing a song at our upcoming holiday party, accompanied by my fairly simple piano.

I have hacked around a bit with My Romance, the Girl from Ipanema, some old Beatles songs, a Stevie Wonder or two, but nothing really sounds very good to me. Perhaps the cheesey, "EZ" piano arrangments are to blame?

I have had much more luck diligently plodding through a recent Steely Dan anthology, but I suspect my singing about drugs and lust for young girls might not exactly flatter her?!?!

Do any of you play the piano or enjoy good old fashioned love songs for piano?

Any suggestions?
"Nature Boy" has simple changes, fantastic melody, and beautiful lyrics. At a neophyte's tempo it sounds great.
Look into Jim Brickman's "Simple Things" fairly simple to play- If I can play it then its easy! And it has a nice sweet rhythm to it when you sing along. You can find it and search Jim Brickman- he has a few other songs that may work well, but I am fond of the "effect" Simple Things has on woman :o) Good luck and let us know how you make out!
Rufus Wainwright's "in a graveyard" from POSES...not exactly uplifting...but very musical...
Forgive me for initially failing to notice your disdain for "cheesy EZ piano arrangements". If you like outstanding charts, I strongly recommend you purchase "The New Real Book" published by Sher Music Co. This is a collection of scores of standards and other classic tunes. (Nature Boy is in this book.) The charts are not sappy EZ charts, but are true to the composers' originals.

As a gigantic bonus, they list the recordings from which the charts are derived in the back of the book, so you can get the record and get some inspiration.

I bought mine in April 1977, and although it is soft and tattered from use, I still find something of interest everytime I pick it up.
How about some Noel Coward or Alec Wilder songs? Coward's songs are funny and clever while Wilder's songs are poignant. The latter are especially easy to sing as the range is not too wide for most people. One of my favorites is "Blackberry Winter".
Skip the singing and learn to orchestrate "Over the Rainbow".

My personal favorite retrospective piece anyway when done as an instrumental (leaves the rest to one's imagination).