My pick for this is Take On Me by A-Ha because I performed this song for Annie in Karaoke Revolution on one of our first dates and it always reminds me of her because of that.
The only clean version on YouTube disabled embedding and has a lame ad at the beginning, but you can find it here:
http://youtu.be/djV11Xbc914 And here's the "literal" version for some embedding love and lols...
Click to view