Ed Bott, an author and Windows expert, has a great post on his site (where he links to a ZDNet post) where he mentions his 10 favorite Windows programs ever.
In this article and accompanying gallery, I list 10 Windows programs I use every day. Every one adds a feature that makes Windows easier to use or can help make you more productive. Each one comes from a company that has proven its ability to support the product and improve it over time. I’ve been using every program on this list for long enough to recommend it without reservation.