Old cc...new collection agency ?

I am in the process of trying to clean up the mess that is my credit. Have sent out what seems to be millions of validation letters... Here is the question though-

I have a credit card account that did not show on my credit report-last payment was made in March 2002. Tonight I got a call from a company and the lady was truly nice :P She told me that her company just recently acquired the account and the balance was $7500. Her company was not licenced to charge intrest and she wanted to make a settlement offer of $2500. I DID not agree to pay anything, nor would I give her any promise to pay. I also asked her about if I paid the account should they be able to validate this debt-would it re open the old account on my credit report and basically re-age it. She told me that it would show as a paid in full per settlement on my report. Is this not a potentially negative? Right now it is past the SOL in Texas (4 years) and is not reporting at all on my credit.

Any experience with this?

Thanks in advance.

Chrissy