Not exactly the word serenade, I just can't think of a better one to describe the kind of songs I'm looking for..

I guess songs along the format of Hey There Delilah [another bad example]

Basically, I need some good songs like these to play acoustic...

Call me Trey.
Blackbird - the beatles. I could play it when i was 11, i think you'll do fine
Quote by Jaymz_515
I pretend I'm a huge spider laying eggs, then when I flush the toilet I fall to floor screaming "MY CHILLLDRENN!! NOOOO!"

If you're flammable and have legs, you are never blocking a fire exit.
- Mitch Hedberg
Try 'those who wait' by Tommy Emmanuel, there are some hard part but they repeat later on so it'll get easier as you go. I think this is what you mean by serenade.