A few of these options require third-party software, but they're all freebies and all easy to use. Most of the tweaks, however, can be accomplished with a few simple clicks. So get ready to make a good OS even better by adding some personal customization touches.

Windows 7 has a lovely blue log-on screen, but it gets a little boring after awhile. Wouldn't it be nice if you could customize it the way you can Windows' desktop wallpaper? You can, without visiting the . All you need is the , a free utility that lets you turn any image into your log-on screen background.

Run the program, click Change Logon Screen, and then navigate to the folder containing the image you want. If it's too large (Windows limits image size to 245KB), Logon Changer will offer to copy and resize it. Once the new background is in place, you can preview it at full-screen size by clicking Test. If you want the old wallpaper back, click Revert to Default Logon Screen.