Have you tried contacting Dell "No Customer Service"? They should be able to help you. Did Dell send a recovery disk or system disk with the computer?
If you want all of Dell's "extra software" this is the route you should follow.
If it was me, I would just download the Windows 7 Pro x64 from the following link and go from there. Dell puts a ton of "bloatware" on their systems. Plus Windows 7 will natively install virtually all the drivers you need, and update them through Windows Update, if necessary.
You can also install
Driver Genius Pro which will update ALL drivers to the very latest versions.
Download the ISO image and burn it to a DVD with ImgBurn at 4x and then use your Product Key to activate it.
http://msft-dnl.digitalrivercontent..../X15-65805.iso