In stave 2, which ghost had more effect on Scrooge?

In stave 2, only one spirit makes an appearance: the Ghost of Christmas Past. The spirit's appearance is important as it provides us with a glimpse of how Scrooge used to be before he became such an ornery old miser. The ghost takes Scrooge back to his miserable childhood, when young Ebenezer was a lonely little boy, hating his boarding school with a passion. But when his beloved sister Fan turns up to take him home for the holidays, Ebenezer is overjoyed. A connection is thus established in young Scrooge's mind between Christmas and happiness, one that will last well into adulthood.
The ghost also introduces us to the charming sight of Scrooge as a young man heartily enjoying Christmas at the house of Mr. Fezziwig, his kindly former employer. But we also see a Scrooge whose soul is becoming corrupted by greed, so much so that his fiancée, Belle, breaks off her engagement with him. Belle is now a happily-married woman, enjoying Christmas with her large family while Scrooge is all alone in a big old drafty house, feeling miserable and being scared half to death by a ghost.
The visit of the Ghost of Christmas Past in stave 2 has a terrible effect upon Scrooge. It makes him feel utterly wretched to see just how far he has fallen in moral terms. Yet the fact that Scrooge was once capable of love, as well as a genuine enjoyment of Christmas, gives us hope that he has the capacity to change his ways.