First, run diagnostics (Fn-Power to start up) to make sure it is not hardware (typ. hard drive or memory).  You may be able to get a "Recovery DVD" that will help you access the recovery partition on your computer, but you may be out of luck if you couldn't get it from the F8 options (i.e., the Recovery Partition may be corrupt, but it doesn't look that way).
I could really use some help.  I don't know a lot about computers and have been searching for answers and just decided to post my own question. My computer got a virus on November 6th.  It caused my files to be hidden.  I waited until Thanksgiving weekend to have my brother check things out.  He fixed that problem, but realized right before we needed to leave that the problem was bigger than that.  For example the Administrative Tools folder is empty.  He suggested to me that I restore back to factory which I have been trying to do (my data is backed up by carbonite).  So when I start my computer and push F8 several times and select "repair your computer" instead of the "system recovery options" window appearing, it says something like...loading windows files (can't remember exactly), but then nothing happens.  I finally gave up and got out of that by using control alt delete.   I have been searching for solutions and have also noticed that my dell datasafe folder is empty as well as the dell support center folder and dell wireless folder. I have been worried that maybe my partition is gone, but couldn't figure out how to find that out.  On a whim I typed partition in the the search programs and files box on the startup menu and disk management came up.  There are four different partitions listed and they all say healthy. Does anyone have any advice for me about how to restore to factory?  It would be much appreciated!!   Thanks! I posted this in another forum and it was suggested that this one would make more sense. 
I need help restoring my inspiron 1545 windows 7 laptop to factory...can't get 
past repair your computer with F8.