I recently discovered a wonderful pdf reader for windows that makes working with pdfLaTeX a breeze: Sumatra PDF. (Yes, it has a whole Watchmen theme going on.) It is lightweight and easy to use. Unlike Acrobat Reader, Sumatra PDF does not lock the file, which allows you to overwrite it without having to close your viewer. Additionally, Sumatra will detect that the pdf has changed and reload the document staying on the same page.
I doubt Sumatra PDF supports all the latest features of Acrobat Reader, so if you have to work with a complex document, you can always fall back to Acrobat. However, for the majority of LaTeX documents it is the perfect solution. Combine Sumatra with TeXnicCenter, and you have a powerful, free solution for writing LaTeX-based documents on Windows.