Cris,
I tend to leave things like that in the same table and set an archived flag or similar, but that's not important.
I think the aim is to automatically trigger the movement (execution of SQL) and there are several options I can think of:
* (if I was on linux) I would run a cron job to run a web page or SQL command. Not sure if you can do something similar on windows scheduler (I know you can schedule stuff, just unsure if you can load a webpage)
* If running MySQL (or MS SQL etc) you should be able to set an event to run the SQL (on MySQL it is 'Events', and in MSSQL you have Jobs that can run SQL)
* put the sql query in a Before Show of a page (like the list of articles or a menu, something reasonably often used) so that when it is opened, the move is done (it's not fully automatic but it would work if nothing else is available)
As for the SQL if you haven't got it already: something like this for Mysql
START TRANSACTION;
INSERT INTO archive (<field names>) SELECT <fields Names> FROM news WHERE deadline < CURDATE();
DELETE FROM news WHERE deadline < CURDATE();
COMMIT;
This can be put in a single SQL Query and executed at once.
Cheers
Eric