David Copperfield, definitely. He is second only Darcy of Pemberley. Copperfield is such a personable voice and character to see the world of Dickens' England through--and--his friends, like Steerforth and Traddles add richness and colorful depth.
I agree that Pip is a magnificent character, but Scrooge is my favorite as well. He is so incredibly ornery before his transformation, and obviously he serves as an example that we all can change, no matter how far gone we seem.
Oh the choices, the choices! Dickens seems to me to be the master of characterisation, and what I love about him (among other things) is his ability to create characters that are so vivid and real, no matter how extraordinary they are. I must admit, curling up with a Dickens is a guilty pleasure that I have. I have to agree with other editors that my favourite character is Pip. He is so much more real than David Copperfield, and I think we sympathise with him more in terms of the way that he faces the realities of life and comes out the other side a better man.
Dickens created so many splendid characters that this is a very difficult question to answer. Since others have already mentioned Pip from Great Expectations, I will put in a good word for Joe Gargery from that same novel. I was recently reminded of Joe and of his relationship with Pip when I read this wonderful moment from the novel, which describes Pip learning to read and write:
One night I was sitting in the chimney corner with my slate, expending great efforts on the production of a letter to Joe. I think it must have been a full year after our hunt upon the marshes, for it was a long time after, and it was winter and a hard frost. With an alphabet on the hearth at my feet for reference, I contrived in an hour or two to print and smear this epistle:—
"MI DEER JO i OPE U R KR WITE WELL i OPE i SHAL SON B HABELL 4 2 TEEDGE U JO AN THEN WE SHORL B SO GLODD AN WEN i M PRENGTD 2 U JO WOT LARX AN BLEVE ME INF XN PIP."
There was no indispensable necessity for my communicating with Joe by letter, inasmuch as he sat beside me and we were alone. But I delivered this written communication (slate and all) with my own hand, and Joe received it as a miracle of erudition.
"I say, Pip, old chap!" cried Joe, opening his blue eyes wide, "what a scholar you are! An't you?"
I have to agree with bullgatortail. I have a special place for Pip in my heart (especially considering the fact I am currently revisiting the novel for a Master's class). Pip's "voice," actions, and good heart keeps him close to my own.
Since Great Expectations was the first Dickens novel I ever read, I still have a soft spot in my heart for Pip. He was imperfect, and his childhood hardly pointed toward successful adulthood, but he prevailed in the end. I also love Ebenezer Scrooge, and Fagin from Oliver Twist.
The eternal optimist in me will put in a vote for Ebenezer Scrooge. He's so deliciously anti-social and determined to shut out every single hint of anything that is remotely human or kind at the beginning of the book. I love watching the transformation of the old grouch into a warm and loving benefactor!
It is so hard to choose! Personally, I have a soft spot for Sydney Carton. I know others won't agree with me, but I think I fell in love with him at 13 and have never gotten over it. Every time I read the book, I still feel for him and enjoy him.