The Christmas Song (Chestnuts Roasting On An Open Fire) by Mel Torme is in Gb at 80 beats per minute and runs 2:21 across 45 bars. It uses 50 chords — Ab11, Ab7, Dbmaj9, Bbm7, Ab7sus2, Ab7aug, Dbmaj7, Fm7, and a few more. The chord diagram changes as the song plays and the words light up as they are sung, so you can strum and sing along without reading ahead.
Want the melody line note by note? The Christmas Song (Chestnuts Roasting On An Open Fire) guitar melody tab.