MAC OS X won't install - prohibition sign at DVD boot!

[OilConsumer]

Ok lately My Mac OS X has crashed on me and I am now stuck on my windows bootcamp partition.
My CD drive is broken so I bought a new external combo drive which works fine! When i go to boot the cd It loads up fine on the alt/option screen however when it goes to the loading the cd (the apple sign) it stays there for a couple of minutes (no loading wheel) and then turns into a prohibition sign!
My mac drive before this was formatted as it was faulty however it is still of the MAC format! (HSF or something)

Please help! If you don't understand me just ask!
Thanks

 

[spinnerlys]

Do you use the gray restore DVDs that came with that Mac or a retail version of Mac OS X like the 29USD Snow Leopard DVD?

 

[OilConsumer]

Do you use the gray restore DVDs that came with that Mac or a retail version of Mac OS X like the 29USD Snow Leopard DVD?

The retail, Install DVD version! I have both the snow leopard and leopard DVD. however my CD drive doesn't like the snow leopard one for some strange reason and doesn't load it, My leopard one however does load up as I said

I didn't receive a restore DVD at all with both of my OS X instal dvd's!

Thanks for replying so quick Did i answer what you were looking for?

 

[OilConsumer]

Also i forgot to mention, both disks have very minor (not deep) scratches on them!