Definately Castlevania. Although Megaman is equally as well known for its catchy tunes, Castlevania had more complex, beautiful, and memorable music. One of the series earlier Of my favorite's were the Super Castlevania renditions of the that town music (from the second and third game) and Bloody Tears (the Chronicles remix was also great), Simon and Richter's Theme (IV and Dracula X, respectively), lesser known mini-symphonys like that clock tower music from III, and Dance of Pales from SOTN.