"Joy to the World" is a popular Christmas carol with lyrics by Isaac Watts and music by G.F.Handel. As of the late 20th century, Joy to the World was the most published Christmas hymn in North America.
For Violin and guitar duet.
Easy.
With downloadable mp3's for audio help (one with both the Violin and guitar and one with guitar only).
With guitar tablature. With melody line. With lyrics.
Pages: three pages (score and Violin part)

Danny Boy is a famous ballad set to an ancient Irish melody with lyrics by English songwriter Frederic Weatherly.
For Violin and guitar duet.
Early intermediate.
With downloadable mp3's for audio help (one with both the Violin and guitar and one with guitar only).
With guitar tablature. With melody line. With lyrics.
Pages: four pages (score and Violin part)

Molly Malone (also known as Cockles and Mussels) is a traditional Irsish song.

For Violin and Guitar duet or Violin Guitar and voice.
With some finger position suggestions. With melody line and lyrics.
With standard notation and tablature. With downloadable mp3 just for audio help.

Easy to early intermediate.
Pages: Three (3) pages,   (2 pages Melody/Violin and Guitar with tab, 1 page Violin part ).

Mauro Giuseppe Sergio Pantaleo Giuliani (27 July 1781 8 May 1829) was an Italian guitarist, cellist, singer, and composer. He was a leading guitar virtuoso of the early 19th century.
This is the second of the set of 16 easy and pleasant duets for violin and guitar composed by Mauro Giulani at 1810.
For Violin and guitar duet.
With downloadable mp3's for audio help (with both the Violin and guitar and one with guitar only for practicing the Violin).  With guitar tablature.
Pages: Six pages (2 pages both Violin and guitar, 1 pages Violin part, 1 page guitar part, 2 pages guitar with guitar tablature part), 3:10' min.

More is one of Ortolani's acclaimed and influential works. It was nominated for the Academy Award for Best Original Song at the 36th Academy Awards in 1964, where it was performed in english by Katyna Ranieri.
For duet  Violin and fingerstyle guitar (acoustic guitar or classical guitar).
Violin : Easy, Guitar : Early intermediate.
With guitar tablature. With lyrics. With melody line.
Pages: 3 pages (2 pages score and 1 page Volin part) 2:05' min.