Father Skywalker said:

My question is-why all of this hatred and dislike and cringe-worthy attiude towards Hayden Christensen????

Because he did a really poor job of making Anakin Skywalker likable in the Prequels. In fact, if anything, he made him downright unlikable. His acting was so poor in those films that they completely failed to live up the the high expectations the fans had of them compared to an amazing film like The Empire Strikes Back.

Obviously, Lucas' directing and writing has a lot to do with this, but Hayden Christensen's did not step up to the plate and give his best performance regardless of what Lucas gave him to work with, and his looks have absolutely nothing to do with the way anyone I've ever met feels about his portrayal of Anakin Skywalker.