So last night I downloaded and ran DTTweak because my defragmenter was not working. I ran the defragmenter and the windows registry cleaner and it was all ok. I shut my computer down and went to sleep. This morning I went on my computer and nothing worked. I have a Dell and my quickset didn't work at all, along with iTunes, Internet Explorer and System Restore. When i try to run System Restore it says that Volume Shadow Copy service used by System Restore is not working... Any ideas??

Type services.msc in the "start search" box. Click on the little gear icon that shows up, then scroll down to Volume Shadow Copy. Right click on it, click properties.
In the 'dropdown box', set it to Automatic, then start the service.