Please provide the complete Sony Vaio model number, then we may be able to help.
Press F8 to bring up the Advanced Boot option menu.
Select Repair the computer (or similar wording).
One of the options under there may be System Recovery.
With the full model number, we can check the Sony web site for the users manual and see what it says.
Edit: Also just found this:
Power on the computer and press F10 several times.
Choose Start Recovery Wizard
Follow the onscreen prompts.