Connecting laptop to tv?

I have connected my laptop to my 32" lcd tv via and s-video lead! the picture on the tv is distorted though and writing is unreadable! what setting to i have to change on my laptop in order to correct this!
Answer
The resolution needs altering from the control panel and then select appearence and themes.after that select the display icon and go to settings which is located top leftish,adjust screen resolution by sliding the pointer...i think lol