you need a tuner card, or a capture card. then just hook it up
http://www.newegg.com/Product/Product.aspx?Item=N82E16815116027 is a ok one. it should come with all the software you need
Whoa whoa whoa, hold on here. You don't need to buy anything. Ive done this before. All you need is a VHS player and a dvd player that can record. and ofcourse a burnable DVD. Hook the VHS player up to the dvd recorder. Then insert a DVD into the dvd recorder. press play on the VHS player and press record on the dvd recorder.
Should work like that!