If you're going to reformat source code, please don't do anything else at the same time
I can't tell you how many times that I have run into this while doing code reviews. Keep your formatting changes and your real code changes separate for the sake of code reviewers, anyone who will have to look at the change history of your source code, and for your own sanity.
As an aside,
Beyond Compare does a pretty good job of ignoring white-space changes if you select the option.