Can you boot the machine to W7 now? If so see my post
HERE. Some laptops have SLIC preactivation built into their BIOS, in which case you would not need the Product Key but it is best to get the key just in case your laptop does not have that feature.
Either buy OEM disks from the laptop manufacturer or Burn a
W7 SP1 Install DVD but understand the OEM disk is different than the official DVD so you really should go to the laptop manufactorer's website and burn all your drivers and special programs (for the touchpad, camera, on-screen volume & brightness displays, etc) and burn those to another CD/DVD. For more detail see my post
HERE (which is also part of the huge thread I linked above).