[jamesmarch]

dateline is epoch time:
http://en.wikipedia.org/wiki/Unix_epoch

I think what you want to do is something like :

SELECT * from vb_thread where dateline <= UNIX_TIMESTAMP('2007-01-01 00:00:00');
This should select all threads created before 2007. UNIX_TIMESTAMP will convert a date to epoch time, which is the format dateline is in.

Also just for the sake of completeness, FROM_UNIXTIME(dateline) will go the other way.

SELECT dateline, FROM_UNIXTIME(dateline) from vb_thread;
will return dateline in epoch and normal yyyymmdd h:i:s format.