It sounds like you missed the HP Tool Partition and deleted the Windows partition instead.
From the little amount of information you provide it doesn't seem you have any choice but to reinstall Windows.
Actually you are right. Never know that a win 7 need a 100mb system reserve partition because never seen this type partition in my desktop or other laptop. So i thought it was for HP recovery. I search in google and now i know windows boot file stayed there. Thanks