Thanks so much for the replies, fireberd and natakuc4.  I located the post that I mentioned re: no code required for MS Works.  It was on the microsoft site, and the following reply was from somone who is identified as a "support engineer."  The reply was as follows:

"Microsoft Works 9.0 doesn’t have a product key for installation. The Office suite on your machine could be a preinstalled trial which is not a part of the works 9.0 suite and requires a product key. You will notice that none of the works applications will prompt for product key when you use them.  The applications included in the works 9.0 suite are:  Works word processor, Works spread sheet, Works calendar, Works database"

Based on the above post on Microsoft's site, I am wondering if his computer came with a preinstalled Office Suite, as well as the Works 9.0, and that perhaps the Office Suite trial is prompting him for the code vs. the Works 9.0.  If that is the case, it would be easy enough to tell him to launch MS Works from his start menu vs. hitting an desktop word processing icon, which may be linked to an Office trial version.

This quoted reply on  Microsoft's site was in direct response to someone who was having exactly the same problem that my son is having -- namely, having the free OEM Works 9, but getting a prompt to enter a product code which was not contained anywhere in his or her software that came with the computer.

In our case, my son definitely had/has Works 9.  It  was preinstalled by Dell on my son's computer, and it also came with a Works 9 CD, which I have has a 20 digit alphanumeric code on the sticker of the plastic envelope containing the disk.  The disk itself has a Microsoft Certificate of Authenticity on the paper envelope containing the disk with an alphanumeric 8 digit code next to the COA logo, and a 14 digit "tracking id" located between 2 bar codes on the same label.

Definitely if we can't figure this out, we'll go the route of one of the software downloads natakuc4's post provided in the links, but the issue my son is having is driving me nuts, esp. when I see this post on Microsoft's site that Works 9 doesn't require a product key, and we definitely have a legitimate and legal OEM copy of Works 9.0 that came with his computer.  Plus, as stated, I have Works on my almost identical (just a little older) Dell laptop and I have never been prompted for a 25 digit code to be able to continue using it.

Thanks for the posts, as well as anyone else who could respond and might know what is going on with my son's Works 9.

Hi Welcome to the Dell forums

I have wrote a few wikis on Microsoft Software and also on Free Software which I find useful. Links are below and you and your son might find some useful information in them.

"Since Works 9.0 doesn't require an activation key, you can just download and install the file. Theoretically, this means that you could also install Works 9.0 without properly owning the software. Please note that this would be illegal and in violation of Microsoft's license agreement." The link to the download is available in the Microsoft Software link below. If it was preinstalled then the computer should already possess a valid license (i.e. he should well be within his rights to download and use this software)

Alternatively he can download and install Microsoft Office 2010 Starter (if he is running Vista or 7). This gives limited functionality Word and Excel and no product key is required. This is again available to download in the Microsoft Software link.

Alternatively he can download and install Open Office. The link for this is in the Free Software for Microsoft Windows below. 

Finally there are some Microsoft Office deals for students available all the time. Get him to google search "The Ultimate Steal" this is a deal Microsoft have with students, he should be able to get a much better deal there than normal. Software there is usually provided as a download and the product key is sent via email.

This does sound like he has the MS Office "Trial" version and it has expired.  I have a Lenovo laptop bought about the same time and it came with the Office Starter" edition which is similar to the old MS Works and has a word processor.  It also had the Office Trial version and I uninstalled that as I had a full, legal, version of MS Office 2003 that I installed.  

He can download the free Open Office suite of programs that are comparable and compatible to MS Office.  That would give him the WordProcessor, Spreadsheet (Excel), Presentation (Powerpoint), etc.  www.openoffice.org

oops, double post - sorry