Hp mini 110 OS compressed.. how to undo?

[flowenz]

I had suddenly compressed my dirve C which has the OS in it. and now i can no longer access my files coz it says that bootmanager error. how do i uncompress the OS since it has an OEM and that i have no cd of it since the OS and OEM was already there when i had bought it. i was not able to make a back-up of my files. please help!

 

[pcfixed]

usualy that error means, "don't waste time, I lost the operating system, so put inside me the vista discs and re-install vista completly"

 

[flowenz]

i dont have the actual cd.. it was already there when bought my Hp mini 110. can i just use any other cd and place the OEM product key? is there no chance that i can fully restore my system back by uncompressing it?