"You're such a cutie, with more than beauty; you've got a lot of
personali-T-N-T"..."Though you're no Mona Lisa, for worlds I'd not
erase (?) my sunny Funny Face"

Hello.

I believe that you're looking for the title song from the musical
"Funny Face."

Complete lyrics for the song "Funny Face" are available on the
Audrey1.com web site:
http://www.audrey1.com/films/funny.html  

Here is an excerpt including the lyrics that you mention:

"...I love your funny face
Your sunny, funny face.
For you're a cutie
With more than beautie.
You've got a lot of
per-son-a-li-tee for me.
 
You fill the air with smiles
For miles and miles and miles
Though you're no Mona Lisa
For worlds I'd not replace,
Your sunny, funny face.
I love your funny face..." 

Source:  Funny Face (1957), hosted by audrey1.com
http://www.audrey1.com/films/funny.html

search strategy: "no mona lisa", "funny face"

I hope this helps.