I don't know that there really is a limit for an actual judgement. You've had the notice and there are no longer any surprises. Credit Card debt is considered an Open Line of Credit. The Statute of Limitations for collection in California is 4 years. That is from the last use or payment. My best advice is to consult an attorney in California.
There is no statute of limitations on a judgment. The only way a judgment can be satisfied is to pay the debt and then it will be removed from your credit report.
18 years
The statute of limitations to sue for a judgment will vary by state and the type of claim. For example, California has a 4-year statute of limitation for breach of written contract and judgments in California last for 10 years and are renewable. A judgment will stay on your credit so long as it is valid.
I believe the statute starts to run from the date of last activity
These are going to be written agreements. As that, it is 4 years in California.
If it is a judgment, that is a court-ordered debt to be paid, there is never a time it will be removed until you pay the court. There is not a statute of limitations in this case. Once you get a receipt for payment from the court, you can take the extra steps to report the payment to the credit bureaus.
There is no statute of limitations on collecting a bad debt. If you owed the debt in 1993 and never paid it, you still owe the debt. A judgment has a statute of limitations that is set by both the federal Fair Credit Reporting Act and laws of the state in which you live, or the credit (or collection agency) does business "...whichever is longer". There are circumstances under which an 11 year old debt could be both reported on your credit, collected and filed suit on. If you suspect the statute of limitations has expired; it gives you a cause for disputing the credit report entry and a defense to the judgment.
I am not familiar with Texas law. The federal statute of limitations is 7 years from the date the judgment was rendered, unless there is a state law that superceeds this statute. Then it would be "whichever is longer".
http://www.creditcards.com/credit-card-news/credit-card-state-statute-limitations-1282.php
These are normally classified as a written agreement. In California that means the limit will be four years from the last acknowledgement of the debt.
The statute of limitations for debts reported on your credit report is 7 1/2 years.
20 years. Based on this page: http://www.creditrepairkitsoftware.com/jugdemen.html