What is the right plus to connect my macbook pro to my TV ?

The question is in the title.

I've got a 2 years old macbook pro and I'd like to connect it to my TV to be able to view on the TV screen the content of my mac (sound and video).

My TV is an old one, not an HD TV.

I know there's the right adaptator out there but there's so much choice and all this HDMi, VGA etc just confuses me : what should I pick ?

Thanks for your help,