In Windows 7, click the Start button, and type "System Configuration" in the search field. Select System Configuration from the list. In Windows 8, simultaneously press the Windows and Q keys to open the global search menu, then type "System Configuration" in the search field before selecting it from the list.
Click the Startup tab in the new dialog window. Scroll down the list and uncheck any programs you would like to disable at startup. Do not uncheck any programs that you are not familiar with, as this can cause problems. Click Apply, then click OK to accept the changes.
In Windows 7, click the Start button, and type "Disk Cleanup" in the search field. Type the same search request in the Windows 8 global search menu if applicable. Wait for the Disk Cleanup utility to diagnose your system. Next, place a check mark beside each category in the pop-up window and click OK. Click the Delete Files button in the pop-up dialog box.