License for lilypond transcriptions of public domain resources

[Voyageur Galactique]

Hi,

I want to publish some lilypond transcriptions of old scores available
as public domain ressources.

I wonder what license is the most adequate. A natural choice would be
to release it as "public domain" but it seems this notion is not
accepted in all country. I think I will release it as CC BY or CC
BY-SA

Another topic is about the pdf documents engraved with lilypond. Since
the fonts used in lilypond are GPLed

I have two different questions :

1/ What license would you personnaly chose and why ?

2/ What license am I allowed to chose for engraved documents (pdf
produced with lilypond).