1. Clean up the disk. Uninstall unneeded programs (especially those that run at start up and/or put something in the system tray), run Disk Cleanup, and defragment the drive. This is a good first step that will almost always take a few seconds off boot time and application loads for any computer.
2. Stomp auto-starting programs. Click Start> Run and type "msconfig" at the prompt. Click the Startup tab and look at all that junk that loads when you launch your PC. Do you really need "Adobe Reader Speed Launch"? Probably not. Turn off anything else that looks useless, but be careful not to disable your anti-virus and important system components.
3. Run a full anti-virus and anti-spyware scan. I would recommend using AVG Free Anti-virus, Spybot - Search and Destroy spyware remover and Ad-aware spyware remover. These programs are all free.
4. Clean up the registry. CCleaner, is free and worth running. It will also remove unused files from your system - allowing Windows to run faster and freeing up valuable hard disk space.
