You have your system set up the way 95% of us do - component straight to the TV. If it is not your speaker distance setting (which I am not thinking it is - .25 sec difference between video and sound seems like a lot), try to use the different sound outputs of the dvd player - even normal...
This problem is usually caused by the DVD player. It is called 'lip sync' and I believe it only affected older DVD players. I haven't read anything about the newer DVD players doing it.
For it to be your center channel, it would have to be in a different state :) Placement isn't going to slow...