You should have got as much Install Media as you ordered and 1 Product Key. The above suggestions are the M$ Recommended manner of use.
However if there are different Product Keys for each Install Disc this Procedure is known by m$ as Bulk Loading and is strictly against the M$ License Agreement. Getting caught doing this will lead to a $250,000.00 Fine from M$ for a First Offense of Piracy and more if it is a Second offense. The Owners Names & Address will also be published in the regular M$ Enforcement Alerts that they Distribute.
If you need to install this onto different Hardware and do have a Volume License but no standardization of Hardware you can use a product like nLite and make Slipstreamed Install Disc's with the Product Key Included.
http://www.nliteos.com/download.html
If you chose to go this way make sure that you read the Guides on their web Site here
http://www.nliteos.com/guide/
OH and [b]Do Not[/b] hand out the Install Media. As that is committing Piracy as well.
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