Speed Up Your Services
Manage the Task Manager: Windows' built-in Task Manager (press Ctrl-Alt-Del and click Task Manager) is great for seeing what your system is up to, but power users will prefer Process Explorer, which shows more details that can help you find a memory leak or troubleshoot a pesky DLL problem.
Nudge your network: If you have network problems, try opening the command prompt (enter cmd in the Start menu's search box) and typing ipconfig /renew to reset your network connection.
Index this, not that: The Windows Search indexer speeds up built-in search functions, but the indexing process itself can consume system resources at inconvenient times. Open Indexing Options in Control Panel (or press the Windows key and type Indexing Options). The resulting dialog box will let you specify which folders or types of data are indexed to avoid bogging down your PC needlessly.
Clean up your startup: If your PC drags its feet during the startup process, press the Windows key and type msconfig to open the System Configuration utility. Check in the Startup tab to see what your machine is loading. Your computer might be loading services or apps that you don't need or want to use on startup.
Sharing is caring: For a little assistance in tracking your shared folders, right-click My Computer (or Computer in Windows 7) and click Manage to bring up the Computer Management tool. Then click Shared Folders to see a list of all of your machine's shared folders, file-sharing sessions, and open files.
Look, Ma, no mouse: XP users should grab Launchy, a free keyboard-driven launcher application that allows you to access programs, files, and even Websites with just a few keystrokes. (Vista and Windows 7 users get the same functionality from the Start menu's search tool.)
Cleaner than you found it: To make sure that your programs uninstall completely, use Revo Uninstaller--it's often more thorough than the programs' own supplied uninstaller routines.
Annoyance buster: If you're tired of User Account Control dialog boxes popping up all the time in Windows Vista, but you don't want to disable the security feature completely, grab TweakUAC to set it to Quiet Mode. Windows 7 has its own UAC controls, but can still benefit from TweakUAC.
Get your hands dirty with Greasemonkey: Optimize your Web browsing with Greasemonkey for Firefox, an add-on that lets you choose among thousands of user-designed scripts for blocking ads, changing the layouts of popular sites, and more. (Variants also exist for Internet Explorer, Chrome, and Safari.)
Work Your Windows Key
Lock your doors (and Windows): Stepping out for a minute? Remember to press Windows-L to lock your computer's screen so that no one can nose around without entering your account password.
Run, Windows, run: To access the Run command easily, press Windows-R.
Keyboard explorer: Want to open a new Windows Explorer window without leaving the keyboard? Press Windows-E.
Declutter your desktop: Access your desktop instantly by pressing Windows-D to hide all open windows. Press Windows-D again to return to where you were.