Mac mini 2006 osx 10.6.8 won't boot from window 7 cd

Please Help.

I got a mac mini 2006 1.66 Ghz core duo with 2 GB of ram for 50 dollars.
So I did a clean installation of snow leopard and upgraded it to 10.6.8.

Then I tried to use boot camp 3.0.4 to install windows 7 32 bit in another partition. Boot camp could divide the hard disk smoothly and asked me to put it windows 7 cd then clicked next. I followed the instruction but it never boot up from window CD.

I am not quite sure why it could not boot from windows 7 cd.

I also tried to press "C- key " at the start to force it to boot from cd.
what it always happened was a white screen for a while then a folder with question mark.

P.S. the internal cd drive was not working. So I use asus external cd drive.



Thank you so much