Help! Upgrsded HD not working

I have a macbook from 2006. Tiger OS. I wanted to upgrade to Snow Leopard as it only has a Core Duo processor. I upgraded the memory to 2GB and got a new 500GB HD. Also got the Snow Leopard OS disk. I boot up and all I get is the blinking folder. Ive tried holding C and Alt but nothing works. The disk always gets shot out. I'm stuck. Please help!

 

Thanks for the quick reply. So I just put my old HD back in to make sure the new memory is working. I decided to try and install Snow Leopard on the old HD and it shot right back out at me after about 10-15 seconds. I guess my CD/DVD drive is shot.

So now my question is can I install Snow Leopard to my new blank HD from an external source, like my external HD or a USB? If so, how? And can I use a Windows computer to get the files onto the external source?

Sorry if this seems trivial. I'm no Mac computer expert.

The new HDD I got is: Western Digital 500 GB Scorpio Blue SATA 3 Gb/s 5400 RPM 8 MB Cache Bulk/OEM Notebook Hard Drive - WD5000BPVT

Thanks


EDIT: Another question: Do I need the Leopard disk in the drive in order to get past the blinking folder? Shouldn't I be able to get to the disk utility no matter what? Maybe not. I'm really confused - I hope all it is is a broken CD/DVD drive...