Thank you for contacting the Windows Genuine Advantage (WGA) program forum. Your question concerning upgrading and recovery media is out of scope for the WGA forum, as well as outside of my area of expertise. In an effort to assist I can say that the bits on the media do need to match the Product Key. Using any XP disk can result in Validation problems. In your case, if you are unable to create a restore disk from the computer, you will need to contact the computer manufacturer (Dell) and obtain a restore disk/get assistance from them on how to do this. Every OEM (like Dell, HP Compaq, Toshiba, Lenovo, Gateway) is different. Which is what makes an OEM license different from a retail license- terms and agreemtents of transferability.
Please do contact Dell before you proceed further.
This may or may not assist you further in your reinstallation. Unofficially, I'd like to remind you to make sure you have all Product Key/software on hand, passwords/website links written, personal files backed up, drivers for your various hardware on hand, including this in case you need it:
Also you may reference the following site for various Telephone Activation Centers: