When you open up a new Finder window, at least in OS X 10.8 Mountain Lion, you’ll see a snapshot of all the files on your Mac. Apple calls this view, “All My Files,” and it’s a good way to just see what you have on your Mac.
It’s also an annoying view if you’re looking for stuff on your Desktop or Documents. If you want to change the default view for any new Finder windows, here’s how.
First, get to the Finder, either with a click on the happy face on the Dock, a Command-Tab button combo on your keyboard, a click on the Desktop, or simply by quitting all the other apps.
Next, click on the Finder menu at the top left of your Mac’s screen. Choose Preferences from the Finder menu (or use Command-Comma), and then click on the General tab at the top. Click on the popup menu “New Finder windows show:” and choose something other than the All My Files, like your Desktop or Documents folder, which are already in the list.
If you choose Other… in the popup menu, you’ll get a standard dialog box to find the folder you’d like for your default new Finder windows. Choose well, young padawan.