Installing mac os snow leopard on a DTR Laptop?

You don't. Even if you could get OS X up and running on that thing (Not impossible, iBoot legacy may be the best bet), you will never get that 9200 working properly. The Radeon 9200 does not have drivers in Snow Leopard. It was only used on PowerPC Macs and Apple dropped those a while ago. Considering the age, audio might be out as well, possibly even the network and wifi, too. I doubt it would be worth it.