You question was, can you be 'sure'. The answer is no, you cannot be sure without knowing Dell's policy on this.
I would speak to someone at Dell.
I've had a Dell, and the difficulty is, when you order a system through Dell online, it is not easy to see from their ordering system whether or not they supply the actual Windows install media. Neither does there seem to be a specific way of making your needs known during the ordering phrase. In my case it was a Windows XP installation CD, but with Windows 7 it will be a DVD. I got mine in 2002, and got the XP CD automatically, but they changed their policy shortly after, and started providing recovery partitions.
So if that is what you want, you need to find out first, and take nothing for granted. If you do speak to them, ask them to tell you, step by step, how to state on the order that you want the disk. By the way, you will likely need a Drivers CD as well. I am not sure how well Win 7 does with drivers.
Mark
Can I be assured that I can receive with the discs that come with
a new Dell desktop a Genuine Microsoft Windows 7 disc that can be used
down the line to perform a "clean Install" on this one computer. I want
more than a "restore System disc", I want a disc to perform "clean
installs" if needed in the future.
Thanks for your reply.
Gary

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