We had earlier blogged about how you could reclaim Disk Space after Windows 7 SP1 install using a command. You can now do it by using the Disk Cleanup utility too, easily!
After installing Windows 7 Service Pack 1, once you are sure that you do not plan to uninstall it, you can remove the service pack installation files easily by running Disk Cleanup utility, and free up disk space.
To do so open the Disk Cleanup Utility. Select the system drive. Click on the “Clean up system files” button.
Here check the Service Pack Backup Files, and click OK to delete these files.
I repeat, you should remove these backup files after a couple of weeks only, once you are sure that things are running smoothly and that you wont need to remove SP1.
Everything you may want to know about Windows 7 Service Pack 1 is available here.