How do you turn off the closed caption?

Try the MENU option on your set or your remote.
Look for a CAPTION option and try to set it to NONE.

Otherwise look for a DISPLAY or INFO butoon on your remote and try to set it to DISPLAY OFF.

If you don't have your user's manual anymore you can usually download one for free from the internet just by googling your tv's model number which is found on a sticker on the back of your TV.

Good luck.