|sounds like you may have deleted the hidden partion, did you format the whole drive or just the C;..?|
if you have deleted the hidden partion you will have to install from a cd, and will not be able to use the oem key.
have you tried downloading the drivers from sony support for your machine, you can use updated win 7 drivers, vista drivers, even some of the older xp drivers...
i find most vaio's take to win 7 very well.
open device manager and update all drivers manually from cd/sony drivers or windows..
i hate computers!
but cant help myself....