Problem with black macbook trying to install snow leopard

Alright, so I just bought snow leopard today and am trying to install it onto my old macbook which is currently running tiger. I bought the $160 something package. When I put the snow leopard disc in, I can hear the disc spinning around in the computer, then suddenly stopping, then starting again. It happens three times before the disc just ejects. I don't have the same problem with playing DVDs or playing items from CDs. Anyone know what's going on?

Hello,
What are your Mac's specs?